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TS-7500
TS-7500.jpg
Product Page
Documentation
Schematic
Mechanical Drawing
FTP Path
Processor
Cavium Networks CNS2132
250MHz ARM9
CPU Datasheet
RAM
64MB DDR
FPGA
Lattice LFXP2 5K
Reprogrammable with Opencore
DIO
33
External Interfaces
USB 2.0 2 hosts, 1 device
1x 10/100 Ethernet
1x I2C/TWI
SPI
8x TTL UART
Internal Storage Media
1x SD
Power Requirements
5VDC, or USB Device
Operates around 2W
Operating Temperature
Cold 0C
Hot 70C
Mechanical
66.04mm X 74.30mm
Height 17.10mm (approx)
Weight 41.6g (approx)

Contents

1 Overview

The TS-7500 was released Jul. 2009 is a small embedded board with a CNS2132 250Mhz ARM9 CPU, Lattice XP2 5k FPGA, 64MB DDR SDRAM, and 4MByte SPI NOR flash chip.

2 Getting Started

A Linux PC is recommended for development. For developers who use Windows, virtualized Linux using VMWare or virtualbox is recommended in order to make the full power of Linux available. The developer will need to be comfortable with Linux anyway in order to work with embedded Linux on the macrocontroller. The main reasons that Linux is useful are:

  • Linux filesystems on the microSD card can be accessed on the PC.
  • More ARM cross-compilers are available.
  • If recovery is needed, a bootable medium can be written.
  • A network filesystem can be served.

Once you have a development environment you should continue in the next few chapters for configuring the board and powering up the system.

2.1 Development Kit and Accessories

The KIT-7500 includes the items that are necessary for development with the TS-7500.

KIT-7500 Contents
Item Description
MSD-2GB-USB-7500 A 2GB Sandisk MicroSD card with a Vivitar SD reader. We recommend Sandisk SD cards as that is what we use for testing. Whenever we receive batches of SD cards from our suppliers, we will pull a few cards for testing to ensure they behave within our expectations. The Vivitar reader is also recommended because it was tested to work with the most SD cards, and it does not have a potentially damaging voltage drop that many consumer SD readers have.
TS-752 The TS-752 demonstrates the flexibility of a Technologic Systems SoM by connecting FPGA driven IO pins to relays, buffered digital inputs, buffered digital outputs, and RS-485 drivers. It also provides an RS-232 driver for the serial console. A TS-ENC750 with a TS-7500 or TS-7550 can provide a complete solution for many embedded applications.
PS-5VDC-REG-8PG The PS-5VDC-REG-8PG is a 5V 2.5A power supply by Condor. Optionally type I or C adapters are available and will ship with the product if ordered to a country where this specific adapter is required. If you require one of these adapters it is recommended to put this in the comments for your order.
CB-DB9Y The CB-DB9Y is a splitter cable used to bring out multiple uarts on the same header.
CB7-05 The CB7-05 is a 5 foot null modem cable. This is commonly used to connect to your workstation.
CB-USB-AMBM This is a USB A male to USB B male which is commonly used to connect the board to your PC as a USB device. This is also used for connecting the TS-9449 to your workstation for a USB to serial console.

The other options include:

Item Description
CN-PC104-40PIN-F The CN-PC104-40PIN-F is the mating connector for the 44 pin male header on the SBC. The 4 omitted pins are the JTAG pins which are only used for factory programming. The pins on this header are a very common 0.100" pitch.
WIFI-N-USB The WIFI-N-USB is an ASUS 802.11N adapter. See the WIFI-N-USB page for more details.
TS-ENC750 The TS-ENC750 provides both the TS-752 and a metal enclosure.
TS-ENC750-DIN The TS-ENC750-DIN is the TS-ENC750 with a DIN rail mount.
TS-752 The TS-752 demonstrates the flexibility of a Technologic Systems SoM by connecting FPGA driven IO pins to relays, buffered digital inputs, buffered digital outputs, and RS-485 drivers. It also provides an RS-232 driver for the serial console. A TS-ENC750 with a TS-7500 or TS-7550 can provide a complete solution for many embedded applications.


2.2 Get a Console

With the development kit you should have the TS-752 which brings out the debug console ttyS0 from the ARM processor as RS232. Custom baseboards should emulate the TS-752 for bringing out console. See the schematics available on the TS-752 page. The console from the UART will use 115200 baud, 8n1 (8 data bits 1 stop bit), and no flow control.


Console from Linux

There are many serial terminal applications for Linux, but 3 common implementations would be picocom, screen, and minicom. These examples assume that your COM device is /dev/ttyUSB0 (common for USB adapters), but replace them with the COM device on your workstation.

Linux has a few applications capable of connecting to the board over serial. You can use any of these clients that may be installed or available in your workstation's package manager:

Picocom is a very small and simple client.

picocom -b 115200 /dev/ttyUSB0

Screen is a terminal multiplexer which happens to have serial support.

screen /dev/ttyUSB0 115200

Or a very commonly used client is minicom which is quite powerful:

minicom -s
  • Navigate to 'serial port setup'
  • Type "a" and change location of serial device to '/dev/ttyUSB0' then hit "enter"
  • If needed, modify the settings to match this and hit "esc" when done:
     E - Bps/Par/Bits          : 115200 8N1
     F - Hardware Flow Control : No
     G - Software Flow Control : No
  • Navigate to 'Save setup as dfl', hit "enter", and then "esc"


Console from Windows

Putty is a small simple client available for download here. Open up Device Manager to determine your console port. See the putty configuration image for more details.

Device Manager Putty Configuration

2.3 Booting up the board

WARNING: Be sure to take appropriate Electrostatic Discharge (ESD) precautions. Disconnect the power source before moving, cabling, or performing any set up procedures. Inappropriate handling may cause damage to the board.

The TS-7500 has 2 ways that it can be powered. The TS-7500 has a 5V line on the #44 Pin Header which can be used to supply power. The TS-752 baseboard can power the 5V rail through the terminal blocks with the PS-5VDC-REG-8PG. The second option is to use the USB Device port which can provide 500mA at 5V.

500px

WARNING: Do not use multiple power connections simultaneously or you may damage the board.

Once you have applied power you should look for console output. The first output is from the bootrom:

  >> TS-BOOTROM - built Oct 12 2011 13:35:38
  >> Copyright (c) 2009, Technologic Systems
  >> Booting from SD card...
  .
  .
  .

This output will only appear on the serial console on the 26 pin header and cannot be redirected like the rest of the booting messages. The "Booting From" message will indicate your boot media. The 3 dots after indicate steps of the booting procedure. The first dot means the MBR was copied into memory and executed. The next two dots indicate that the MBR executed and the kernel and initrd were found and copied to memory.

When you first apply power to the board, the logic values on the MODE1 and MODE2 pins are latched. These signals decide if you boot from the MicroSD, onboard flash, or offboard flash. Keep in mind this only includes the initial boot of the kernel and initrd, but once the initrd is booted you can load the Debian partition from theSD, USB drive, or an NFS root regardless of your initially booted media. Most common cases will boot from only one media.

If you are using the TS-752 the MODE1 and MODE2 pins are controlled by JP1 and JP2. Connecting the jumper will pull these to 0. The MODE1 and MODE2 signals both have 4.7k pull-ups. For a logic 0 om a custom, baseboard these should be pulled to ground with a 680ohm resistor.

Boot Modes
Booot Device MODE1 MODE2
Onboard Flash 1 1
SD Card 0 1
Offboard Flash 1 0

2.4 Initrd / Busybox

After the board is first booted you will be at this shell:

  >> TS-BOOTROM - built Oct 12 2011 13:35:38
  >> Copyright (c) 2009, Technologic Systems
  >> Booting from SD card...
  .
  .
  .
  >> Booted from: SD card                 Booted in: 3.93 seconds
  >> SBC Model number: TS-XXXX            SBC Sub-model number: 0
  >> CPU clock rate: 250MHz               RAM size: 64MB
  >> NAND Flash size: 256MB               NAND Flash Type: 0xdcec (Samsung)
  >> MAC number: 00:D0:69:4F:6F:04        SBC FPGA Version: 7
  >> Temperature Sensor: 37.500 degC      MODE1 bootstrap: ON
  >> RTC present: YES                     Date and Time: Jan  1 1970 00:00:03
  >> MODE2 bootstrap: OFF                 SD card size: 1886MB
  >> Offboard SPI flash type: Micron      Offboard SPI flash size: 8MB
  >> XUARTs detected: 3                   CAN present: NO
  >> Linux kernel version: 2.6.24.4       Linux kernel date: Jun 8 2011
  >> Bootrom date: Oct 12 2011            INITRD date: Dec 27 2011
  >> ts7500ctl date: Jun  8 2011          sdctl date: Jun  8 2011
  >> canctl date: Jun  8 2011             nandctl date: Aug 15 2011
  >> spiflashctl date: Aug 15 2011        xuartctl date: Aug 15 2011
  >> dioctl date: Feb 10 2011             spictl date: Jan 24 2011
  >> dmxctl date: Jun  8 2011             busybox date: Jun 30 2010 (v1.14.2)
  >> ts7500.subr date: Jun 10 2011        daqctl date: Aug 15 2011
  >> linuxrc date: Aug 31 2011            rootfs date: Jan  1 1970
  >> MBR date: Jul 14 2009
  
  Type 'tshelp' for help
  # 
Note: Your version dates may be different depending on ship date and the image used.

This is a busybox shell which presents you with a very minimalistic system. While this has access to many Debian applications, it is important to note that this is not Debian. This environment will allow very fast boot times closer to 2-4 seconds, while Debian takes closer to 30-45 seconds but provides an init system and a more standard environment. As described in the previous section, the kernel and initrd are copied into RAM so any changes to this filesystem are temporary. You can commit changes using the "save" command.

For most development you will want to boot to the Debian filesystem which can be reached by typing "exit" through the serial console, or by relinking the linuxrc script to make the board automatically boot to Debian:

rm linuxrc; ln -s /linuxrc-sdroot /linuxrc; save

The linuxrc-sdroot script will actually mount and boot to the Debian filesystem on the SD or XNAND depending which device you used to boot. You can boot to a different Debian partition by using one of the other linuxrc scripts:

Script Function
linuxrc-fastboot (default) Boots immediately to a shell in ramdisk. This will mount whichever boot medium you have selected to /mnt/root/. When you type 'exit', it will boot to that medium.
linuxrc-nandmount Same as the linuxrc-fastboot script, but will mount and boot the debian partition from NAND.
linuxrc-sdmount Same as the linuxrc-fastboot script, but will mount and boot the debian partition from SD.
linuxrc-sdroot Boots immediately to the Debian stored on either SD or NAND depending on which media the SBC was booted from.
linuxrc-sdroot-readonly Same as linuxrc-sdroot, except it will mount the Debian partition read only while creating a unionfs with a ramdisk. Changes will only happen in memory and not on disk.
linuxrc-usbroot Mounts the first partition of the first detected USB mass storage device and boots there.

Once you have booted to Debian you can force the boot process to stop in the fastboot shell/initd on next bootup with:

touch /fastboot

The small default initrd is only 2Mbyte but there is space for approximately 800 Kbyte of additional user applications. This constraint is important if you are running your application without Debian, but only from the initrd. If you have the Debian partition available you can access that partition under /mnt/root/ to run your application.

The compiled instance of busybox includes several internal commands listed below:

   # /bin/busybox --help
   BusyBox v1.14.2 (2009-08-07 14:43:48 MST) multi-call binary
   Copyright (C) 1998-2008 Erik Andersen, Rob Landley, Denys Vlasenko
   and others. Licensed under GPLv2.
   See source distribution for full notice.
   
   Usage: busybox [function] [arguments]...
      or: function [arguments]...
   
           BusyBox is a multi-call binary that combines many common Unix
           utilities into a single executable.  Most people will create a
           link to busybox for each function they wish to use and BusyBox
           will act like whatever it was invoked as!
   
   Currently defined functions:
           [, [[, ash, basename, cat, chgrp, chmod, chown, chroot, cmp, cp,
           cpio, cttyhack, cut, date, dd, depmod, devmem, df, dirname, dmesg,
           du, echo, egrep, env, expr, false, fdisk, fgrep, find, grep, gunzip,
           gzip, halt, head, hostname, hush, ifconfig, insmod, kill, killall,
           ln, login, ls, lsmod, md5sum, mdev, mkdir, mknod, modprobe, more,
           mount, msh, mv, netstat, ping, pivot_root, poweroff, printf, ps,
           pwd, reboot, rm, rmdir, rmmod, route, rx, sed, setconsole, setsid,
           sh, sleep, stty, sync, tail, tar, telnetd, test, tftp, top, tr,
           true, udhcpc, umount, unzip, usleep, uudecode, uuencode, vi, wget,
           xargs, yes, zcat

Also on the initrd are the TS specific applications: sdctl, spiflashctl, nandctl, daqctl, ts7500ctl, canctl, and xuartctl. We also provide the ts7500.subr which provides the following functions:

 cvtime()
 usbload()
 sdsave()
 spiflashsave()
 save()
 sd2spiflash()
 spiflash2sd()
 setdiopin()
 getdiopin()
 setrelay()
 setout()
 getin()
 tshelp()
 gettemp()

To use these functions you must source the subr file:

. /ts7500.subr
## or from Debian 
# . /initrd/ts7500.subr
tshelp

3 Debian Configuration

For development it is recommended to go boot to the full Debian where there is plenty of space for development work. Debian provides many more packages and a much more familiar environment for users already versed in Debian. Once here you can use apt-get to install/remove packages, configure the network, and perform other common tasks.

3.1 Configuring the Network

From almost any Linux system you can use "ip" or the ifconfig/route commands to initially set up the network. To configure the network interface manually you can use the same set of commands in the initrd or Debian.

# Bring up the CPU network interface
ifconfig eth0 up
 
# Or if you're on a baseboard with a second ethernet port, you can use that as:
ifconfig eth1 up
 
# Set an ip address (assumes 255.255.255.0 subnet mask)
ifconfig eth0 192.168.0.50
 
# Set a specific subnet
ifconfig eth0 192.168.0.50 netmask 255.255.0.0
 
# Configure your route.  This is the server that provides your internet connection.
route add default gw 192.168.0.1
 
# Edit /etc/resolv.conf for your DNS server
echo "nameserver 192.168.0.1" > /etc/resolv.conf

Most commonly networks will offer DHCP which can be set up with one command:

Configure DHCP in Debian:

# To setup the default CPU ethernet port
pump -i eth0
# Or if you're on a baseboard with a second ethernet port, you can use that as:
pump -i eth1

Configure DHCP in the initrd:

udhcpc -i eth0
# Or if you're on a baseboard with a second ethernet port, you can use that as:
udhcpc -i eth1

To make your network settings take effect on startup in Debian, edit /etc/network/interfaces:

 # Used by ifup(8) and ifdown(8). See the interfaces(5) manpage or 
 # /usr/share/doc/ifupdown/examples for more information.          
                                                                   
 # We always want the loopback interface.                          
 #                                                                 
 auto lo                                                           
 iface lo inet loopback                                            
                                                                   
 auto eth0                                                         
 iface eth0 inet static                                            
   address 192.168.0.50                                            
   netmask 255.255.255.0                                           
   gateway 192.168.0.1                                             
 auto eth1                                                         
 iface eth1 inet dhcp

In this example eth0 is a static configuration and eth1 receives its configuration from the DHCP server. For more information on network configuration in Debian see their documentation here.

To make your changes permanent in the initrd you will need to edit the linuxrc script. Use the same commands you would use to manually configure it and place them over the current ifconfig calls.

3.2 Installing New Software

Debian provides the apt-get system which lets you manage prebuilt applications. Before you do this you need to update Debian's list of package versions and locations. This assumes you have a valid network connection to the internet.

Debian Lenny has been moved to archive so you will need to update /etc/apt/sources.list to contain these two lines:

 deb http://archive.debian.org/debian lenny main
 deb-src http://archive.debian.org/debian lenny main

Now you can update the local cache of packages:

apt-get update

For example, if you wanted to install picocom you could use the apt-cache command to search the local cache of Debian's packages.

 root@ts7500:~# apt-cache search picocom
 picocom - minimal dumb-terminal emulation program
            

You can often find the names of packages from Debian's wiki or from just searching on google as well.

Once you have the package name you can use apt-get to install the package and any dependencies. This assumes you have a network connection to the internet.

apt-get install picocom
# You can also chain packages to be installed
apt-get install picocom nano vim

For more information on using apt-get refer to Debian's documentation here.

3.3 Setting up SSH

On our boards we include the Debian package for openssh-server, but we remove the automatically generated keys for security reasons. To regenerate these keys:

dpkg-reconfigure openssh-server

Make sure your board is configured properly on the network, and set a password for your remote user. SSH will not allow remote connections without a password or a shared key.

passwd root

You should now be able to connect from a remote Linux or OSX system using "ssh" or from Windows using a client such as putty.

3.4 Starting Automatically

From Debian the most straightforward way to add your application to startup is to create a startup script. This is an example simple startup script that will toggle the red led on during startup, and off during shutdown. In this case I'll name the file customstartup, but you can replace this with your application name as well.

Edit the file /etc/init.d/customstartup to contain this:

 #! /bin/sh
 # /etc/init.d/customstartup
 
 case "$1" in
   start)
     /usr/local/bin/ts7500ctl --redledon
     ## If you are launching a daemon or other long running processes
     ## this should be started with
     # nohup /usr/local/bin/yourdaemon &
     ;;
   stop)
     /usr/local/bin/ts7500ctl --redledoff
     ;;
   *)
     echo "Usage: customstartup start|stop" >&2
     exit 3
     ;;
 esac
 
 exit 0
Note: The $PATH variable is not set up by default in init scripts so this will either need to be done manually or the full path to your application must be included.

To make this run during startup and shutdown:

update-rc.d customstartup defaults

To manually start and stop the script:

/etc/init.d/customstartup start
/etc/init.d/customstartup stop

To make your application startup from the initrd you only need to add the required lines (no need for the Debian init syntax) to the linuxrc script. Usually the best place to add in your application is right after /mnt/root/ is mounted so the Debian libraries and applications are available.

3.5 802.11 Wireless Network

This board optionally supports 802.11 through the #WIFI-N-USB module which will create the interface ra0 using the rt3070sta module. You can load this by running:

modprobe rt3070sta-7500

Scan for a network

ifconfig ra0 up
 
# Scan for available networks
iwlist ra0 scan

In this case I'm connecting to "default" which is an open network:

          Cell 03 - Address: c0:ff:ee:c0:ff:ee
                    Mode:Managed
                    ESSID:"default"
                    Channel:2
                    Encryption key:off
                    Bit Rates:9 Mb/s

To connect to this open network:

iwconfig ra0 essid "default"

You can use the iwconfig command to determine if you have authenticated to an access point. Before connecting it will show something similar to this:

# iwconfig ra0
rausb0    RT73 WLAN  ESSID:off/any  Nickname:""
          Mode:Auto  Frequency=2.412 GHz  Bit Rate:54 Mb/s   
          RTS thr:off   Fragment thr:off
          Encryption key:off
          Link Quality=0/100  Signal level:-121 dBm  Noise level:-115 dBm
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

If you are connecting using WEP, you will need to define a network key:

iwconfig ra0 essid "default" key "yourpassword"

If you are connecting to WPA, you will need to use wpa_passphrase and wpa_supplicant:

wpa_passphrase the_essid the_password > /etc/wpa_supplicant_custom.conf

You will need to edit the /etc/wpa_supplicant_custom.conf file so the network block contains "proto=RSN". For example:

  network={
        ssid="default"                     
        proto=RSN
        #psk="yourpassword"
        psk=your-key-encoded                                                
  }

The default image contains a patched wpa_supplicant for an older device, but for the WIFI-N-USB you will need to remove this and use the version from Debian:

mv /usr/local/bin/wpa_supplicant /usr/local/bin/wpa_supplicant.old
apt-get update && apt-get install wpasupplicant #This assumes a proper internet connection is established
 
# reset the shell to find the new wpa_supplicant
exec bash
 
# Verify that it is the correct version (0.6.4):
wpa_supplicant -v

Now that you have the configuration file, you will need to start the wpa_supplicant daemon:

wpa_supplicant -irausb0 -Dralink -c/etc/wpa_supplicant_custom.conf -B

When you have successfully connected, it will list an "Access Point" bssid, and a "Link Quality" of greater than 0/100.

# iwconfig rausb0
rausb0    RT73 WLAN  ESSID:"default"  Nickname:""
          Mode:Managed  Frequency=2.417 GHz  Access Point: c0:ff:ee:c0:ff:ee  
          Bit Rate=11 Mb/s   
          RTS thr:off   Fragment thr:off
          Encryption key:off
          Link Quality=63/100  Signal level:-70 dBm  Noise level:-99 dBm
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

Now you are connected to the network, but this would be close to the equivilant of connecing a network cable. To connect to the internet or talk to your internal network you will need to configure the interface. See the #Configuring the Network for more information.

4 Backup / Restore

If you are using a Windows workstation there is no support for writing directly to block devices. However, as long as one of your booting methods still can boot a kernel and the initrd you can rewrite everything by using a usb drive. This is also a good way to blast many stock boards when moving your product into production. You can find more information about this method with an example script here.

4.1 MicroSD Card

MicroSD.png Click to download the latest 2GB SD card image.

Once downloaded you can decompress the image using bzip2:

bzip2 -d 2gbsd-noeclipse-latest.dd.bz2

The resulting file will be "2gbsd-noeclipse-latest.dd".

For imaging the SD card we recommend using a Linux or similar operating system that allows you to access a block device using dd. We do not support rewriting the SD card from Windows.

If you are reprogramming the SD card from your workstation you will also need to determine the SD card device. Once you have connected the SD card to your workstation you can usually find the correct block device in the output of "dmesg". For example:

 [  309.498834] sd 8:0:0:0: [sdb] 3862528 512-byte logical blocks: (1.97 GB/1.84 GiB)
 [  309.519814] sd 8:0:0:0: [sdb] Write Protect is off
 [  309.519818] sd 8:0:0:0: [sdb] Mode Sense: 03 00 00 00
 [  309.519819] sd 8:0:0:0: [sdb] Assuming drive cache: write through
 [  309.536025] sd 8:0:0:0: [sdb] Assuming drive cache: write through
 [  309.536029]  sdb: sdb1 sdb2 sdb3
 [  309.559672] sd 8:0:0:0: [sdb] Assuming drive cache: write through
 [  309.559676] sd 8:0:0:0: [sdb] Attached SCSI removable disk

On this system my SD card block device is /dev/sdb, but your system will likely be different. The block devices are allocated in order by the letter so the next USB drive connected would be /dev/sdc. On some newer kernels you will see '/dev/mmcblk0' as the block device and '/dev/mmcblk0p1' for the first partition. For these examples I will use the '/dev/mmcblk0' format.

WARNING: Many distributions will name your hard drive something like /dev/sda or /dev/hda which will have the same naming scheme as an SD card or a USB drive. Make sure you are aware which device is which before writing the disk. Technologic Systems is not responsible for any data lost/destroyed because of improper command execution.


WARNING: If you are working with the SD card from your workstation, keep in mind that most Linux distributions will mount the partitions that they can as soon as the drive is inserted. This is desirable if you want to open the filesystem, but for dealing directly with the block device for performing backups or restoring an image this is dangerous to your data.

To verify if your workstation has mounted the block device on insertion:

cat /proc/mounts
# look for your SD card block device to see if this is already mounted.

If the block device did automatically mount, you will need to refer to your distribution's documentation for disabling automounting. For example, this is Ubuntu's documentation on disabling automounting. If you are not using a graphical Linux system this should not be a concern, but make sure no filesystems are mounted read only or read write while writing or reading an image.

For backing up or restoring any images from the board you will need to make sure you do not have any partitions mounted. On the default configuration you can write an image from the initrd after unmounting /mnt/root:

umount /mnt/root/

Restore from Workstation

To write the latest image or restore to stock you would use the dd command. This will perform a byte for byte copy from our image. This contains the MBR boot code with the partition tables, the kernel, initrd, and Debian filesystem. No other formatting or partitioning is needed.

Write an image to the entire SD card:

dd if=/path/to/backup.dd of=/dev/mmcblk0 bs=4M conv=fsync

If you want to write a new kernel, but not an entire image you can rewrite the second partition:

dd if=/path/to/zImage bs=4M of=/dev/mmcblk0p2 conv=fsync

Backup from Workstation

To backup an entire SD card image:

dd if=/dev/mmcblk0 of=/path/to/backup.dd bs=4M

This will create a dd file the size of the card.

Note: A 2GB MicroSD card from one manufacturer will likely not be the exact same size as another manufacturer's 2GB MicroSD card. Our partition layouts by default leave the last 10% of the images unallocated to account for this. As long as you use our partition layout you should not need to be concerned with this, but if you create your own layout we strongly recommend leaving 10% of the disk unallocated.

Once you have the disk image you will want to trim this to the last partition so the image doesn't contain the free space at the end of the disk. To get the last sector you would use fdisk:

 fdisk -ucl /dev/sdb
 
 Disk /dev/sdb: 1977 MB, 1977614336 bytes
 61 heads, 62 sectors/track, 1021 cylinders, total 3862528 sectors
 Units = sectors of 1 * 512 = 512 bytes
 Sector size (logical/physical): 512 bytes / 512 bytes
 I/O size (minimum/optimal): 512 bytes / 512 bytes
 Disk identifier: 0x00000000
 
    Device Boot      Start         End      Blocks   Id  System
 /dev/sdb1             512        8703        4096   83  Linux
 /dev/sdb2            8704       15871        3584   da  Non-FS data
 /dev/sdb3           16896       20991        2048   da  Non-FS data
 /dev/sdb4           25088     3170815     1572864   83  Linux

On this SD card the end of the partition is 3170815 sectors. As the sectors each contain 512B the image is 1623457280 bytes. You can use the truncate command to correct the image size:

# This is an example - check your image with fdisk
truncate backup.dd --size=1623457280

Keep in mind these numbers are an example and are not necessarily representative of your image.

If you would like to backup just the Kernel partition, you would grab partition 2.

dd if=/dev/mmcblk0p2 of=/path/to/zImage bs=32k

Restore From the SBC

To write the latest image or restore to stock you would use the dd command. This will perform a byte for byte copy from our image. This contains the MBR boot code with the partition tables, the kernel, initrd, and Debian filesystem. No other formatting or partitioning is needed.

Write an image to the entire SD card:

dd if=/path/to/image-latest.dd of=/dev/nbd9 conv=fsync

Kernel

dd if=/mnt/root/zImage of=/dev/nbd7 conv=fsync

Backup From the SBC

To backup an entire SD card image:

# Determine the block size
eval $(sdctl)
dd if=/dev/nbd5 of=/path/to/backup.dd bs=512 count=$cardsize_sectors conv=sync && sync

This will create an image file the size of the card.

Note: A 2GB MicroSD card from one manufacturer will likely not be the exact same size as another manufacturer's 2GB MicroSD card. Our partition layouts by default leave the last 10% of the images unallocated to account for this. As long as you use our partition layout you should not need to be concerned with this, but if you create your own layout we strongly recommend leaving 10% of the disk unallocated.

Once you have the disk image you will want to trim this to the last partition so the image doesn't contain the free space at the end of the disk. To get the last sector you would use fdisk:

 fdisk -ucl /dev/sdb
 
 Disk /dev/sdb: 1977 MB, 1977614336 bytes
 61 heads, 62 sectors/track, 1021 cylinders, total 3862528 sectors
 Units = sectors of 1 * 512 = 512 bytes
 Sector size (logical/physical): 512 bytes / 512 bytes
 I/O size (minimum/optimal): 512 bytes / 512 bytes
 Disk identifier: 0x00000000
 
    Device Boot      Start         End      Blocks   Id  System
 /dev/sdb1             512        8703        4096   83  Linux
 /dev/sdb2            8704       15871        3584   da  Non-FS data
 /dev/sdb3           16896       20991        2048   da  Non-FS data
 /dev/sdb4           25088     3170815     1572864   83  Linux

On this SD card the end of the partition is 3170815 sectors. As the sectors each contain 512B the image is 1623457280 bytes. You can use the truncate command to correct the image size:

# This is an example - check your image with fdisk
# truncate is a Debian command and will not be available from busybox
truncate backup.dd --size=1623457280

Keep in mind these numbers are an example and are not necessarily representative of your image.

If you would like to backup just the kernel partition, you would grab partition 2.

dd if=/dev/mmcblk0p2 of=/path/to/zImage bs=32k

4.2 SPI Flash

This needs to be done directly on the SBC. You can find the latest SPI image here. Once downloaded you can decompress the image using bzip2:

bzip2 -d 4mb-spiflash-latest.dd.bz2

Some of this series contains a 4MB SPIflash embedded on the board that can be written to by specifying lun 0, or "-l 0" which will use that chip select. The offboard flash found on various baseboards, or console boards like the TS-9448 or TS-9449 can be written to using lun 1, or "-l 1".

Backup

Backup the entire SPI flash containing the MBR, Kernel, and initrd

spiflashctl -l 1 -R 64 -z 65536 > spiflash.dd

Backup only the Kernel

spiflashctl -l 1 -R 4095 -z 512 -k part1 > /temp/zImage

Backup only the Initrd

spiflashctl -l 1 -R 32 -z 65536 -k part2 > /temp/initrd

Restore

Write the entire SPI flash containing the MBR, Kernel, and initrd

spiflashctl -l 1 -W 64 -z 65536 -i /path/to/4mb-spiflash-latest.dd

Write a new Kernel

spiflashctl -l 1 -W 4095 -z 512 -k part1 -i /temp/zImage

Write a new Initrd

spiflashctl -l 1 -W 32 -z 65536 -k part2 -i /temp/initrd

4.3 Fastboot Recovery Commands

Since the Aug 5 2010 release, scripts have been added to the bash subroutine to ease in saving, recovering, and moving around images from one flash device to another. Below is a brief list of the commands that are provided as well as what they do. See the file /ts7500.subr (or /initrd/ts7500.subr from full Debian) for more information on the commands and what they do.

 save - Copy current initrd ramdisk to the media that the SBC is booted from
 sdsave - Copy current initrd ramdisk to mSD card
 sd2nand - Copy mSD kernel and initrd to NAND
 sd2flash - Copy mSD kernel and initrd to on-board SPI flash
 sd2flash1 - Copy mSD kernel and initrd to off-board SPI flash
 flash2sd - Copy booted SPI flash kernel and initrd to mSD card
 flashsave - Copy current initrd ramdisk to on-board flash (TS-7500 only)
 flash1save - Copy current initrd ramdisk to off-board flash (TS-752 or TS-9448)
 flash2flash - Copy booted SPI flash kernel and initrd to opposing SPI flash device (on-board to off-board and vice versa)
 flashallsave - Copy current initrd ramdisk to all SPI flash (on-board and off-board)
 nand2sd - Copy NAND flash kernel and initrd to mSD card
 nandsave - Copy current initrd ramdisk to NAND
 nand2flash - Copy NAND flash kernel and initrd to off-board flash
 flash2nand - Copy booted SPI flash kernel and initrd to NAND
 recover - Attempt to copy booted kernel and initrd to all other available flash devices

5 Software Development

Most of our examples are going to be in C, but Debian will include support for many more programming languages. Including (but not limited to) C++, PERL, PHP, SH, Java, BASIC, TCL, and Python. Most of the functionality from our software examples can be done from using system calls to run our userspace utilities. For higher performance, you will need to either use C/C++ or find functionally equivalent ways to perform the same actions as our examples.

The most common method of development is directly on the SBC. Since debian has space available on the SD card, we include the gnu compiler collection package which comes with everything you need to do C/C++ development on the board. To get started, this is how you could build a hello world application:

nano hello.c

This will open a blank file with nano which is a very simplistic editor. Enter in your hello world code:

#include <stdio.h>
 
int main()
{
     printf("Hello World!\n");
     return 0;
}

To save this in the editor, press "ctrl+x", type "y" to save and press enter to leave the editor. You you can use the gcc tools to compile this:

gcc hello.c -o hello
 
./hello

This should return your "Hello World!" text. There are far more tools you can learn to aid in your development as well:


Editors

Vim is a very common editor to use in Linux. While it isn't the most intuitive at a first glance, you can run 'vimtutor' to get a ~30 minute instruction on how to use this editor. Once you get past the initial learning curve it can make you very productive. You can find the vim documentation here.

Emacs is another very common editor. Similar to vim, it is difficult to learn but rewarding in productivity. You can find documentation on emacs here.

Nano while not as commonly used for development is the easiest. It doesn't have as many features to assist in code development, but is much simpler to begin using right away. If you've used 'edit' on Windows/DOS, this will be very familiar. You can find nano documentation here.

Compilers

We only recommend the gnu compiler collection. There are many other commercial compilers which can also be used, but will not be supported by us. You can install gcc on most boards in Debian by simply running 'apt-get update && apt-get install build-essential'. This will include everything needed for standard development in c/c++.

You can find the gcc documentation here. You can find a simple hello world tutorial for c++ with gcc here.

Build tools

When developing your application typing out the compiler commands with all of your arguments would take forever. The most common way to handle these build systems is using a make file. This lets you define your project sources, libraries, linking, and desired targets. You can read more about makefiles here.

If you are building an application intended to be more portable than on this one system, you can also look into the automake tools which are intended to help make that easier. You can find an introduction to the autotools here.

Cmake is another alternative which generates a makefile. This is generally simpler than using automake, but is not as mature as the automake tools. You can find a tutorial here.

Debuggers

Linux has a few tools which are very helpful for debugging code. The first of which is gdb (part of the gnu compiler collection). This lets you run your code with breakpoints, get backgraces, step forward or backward, and pick apart memory while your application executes. You can find documentation on gdb here.

Strace will allow you to watch how your application interacts with the running kernel which can be useful for diagnostics. You can find the manual page here.

Ltrace will do the same thing with any generic library. You can find the manual page here.

5.1 Cross Compiling

While the onboard tools are recommended for development, some applications can reach a size where the compile time is not feasible. An example of this is the Linux Kernel which will take 5-10 minutes to compile on a typical X86 workstation, but it can take 7-15 hours to compile on the SBC depending on several factors. A hello world application in comparison will take only a couple seconds on the board.

Cross compiling has a complication in that the onboard libraries do not exactly match the cross compiler environment. Debian has around 15,000 to 20,000 packages available in the apt repositories, and there is no way to feasibly build a cross compiler to account for all of these libraries. If you are cross compiling you will need to have your application entirely self contained and linking to any third party libraries in your build system.

There are two toolchains that can be used depending on your application. Most applications should use this toolchain which compiles applications to use Debian's glibc 2.7 libraries. You can compile using this toolchain by calling the version of gcc in the archive:

 usr/local/opt/crosstool/arm-linux/gcc-3.3.4-glibc-2.3.2/bin/arm-linux-gcc

The second toolchain is using the uClibc compiler here. uClibc has some limitations in order to reduce the binary size, but will also work for many simple C applications. All of our included ctl applications are built using this toolchain. Using this compiler also allows you to compile binaries that do not rely on the Debian filesystem. While this does have a g++ compiler, we do not include any c++ support in the initrd. You can compile with this toolchain by calling this version of gcc in the archive:

 arm-uclibc-3.4.6/bin/arm-linux-uclibc-gcc
Note: We do not support third party cross compilers.
Note: The provided cross compilers are only for C development.

5.2 Kernel Compile Guide

The TS kernel is built from the same Linux sources Cavium Networks has tested and used on their CPU evaluation boards. There are no Technologic Systems specific drivers or kernel support implemented. Instead, there has been userspace driver support implemented for the SPI NOR flash, MicroSD cards, XNAND drive, battery-backed real-time clock, XUART serial port channels, watchdog, and GPIO pins. This allows easy migration to newer kernels when either Cavium or the mainline Linux kernel community creates them. In the past, constant Linux-internal API redesign required rewriting and revisiting custom drivers with each new kernel revision, in effect locking customers in to whatever kernel version was released and tested during initial product release. Being free to update to newer kernels in the future allows easier support of the new USB devices as those drivers tend to only be developed for the newest kernel sources.

We provide Linux 2.6.24 as the supported kernel.

WARNING: Backup any important data on the board before replacing the kernel.

For adding new support to the kernel, or recompiling with more specific options you will need to have an X86 compatible linux host available that can handle the cross compiling. Compiling the kernel on the board is not supported or recommended. Before building the kernel you will need to install a few support libraries on your workstation:

Prerequisites

RHEL/Fedora/CentOS:

yum install ncurses-devel ncurses
yum groupinstall "Development Tools" "Development Libraries"

Ubuntu/Debian:

apt-get install build-essential libncurses5-dev libncursesw5-dev

For other distributions, please refer to their documentation to find equivalent tools.

Set up the Sources and Toolchain

# Download the cross compile toolchain (OABI)from Technologic Systems:
wget ftp://ftp.embeddedarm.com/ts-arm-sbc/ts-7500-linux/cross-toolchains/crosstool-linux-arm-uclibc-3.4.6.tar.gz
 
#Extract to current working directory:
tar xvf crosstool-linux-arm-uclibc-3.4.6.tar.gz
 
#Download the Cavium Sources
wget ftp://ftp.embeddedarm.com/ts-arm-sbc/ts-7500-linux/sources/linux-2.6.24-ts-src-aug102009.tar.gz
 
#Extract the Kernel Sources
gzip -dc linux-2.6.24-ts-src-aug102009.tar.gz | tar xf -
 
cd linux-2.6.24-cavium/
 
export ARCH=arm
export CROSS_COMPILE=../arm-uclibc-3.4.6/bin/arm-linux-
 
# This sets up the default configuration for the Cavium CPU
make ts7500_defconfig
Note: If you get the message "Make: *** mixed implicit and normal rules. Stop." Then you may need to downgrade your version of make.
make menuconfig

This will bring up a graphical menu where you can edit the configuration to include support for new devices. For Example, to include CIFS support, use the arrow and Enter keys to navigate to Filesystems -> Network File Systems -> CIFS Support. Press "y" to include CIFS support into the kernel (alternatively, you could modularize the feature with "m" so you can enable or disable the module on demand which will also enable you to simply copy/paste the cifs.ko into the correct path in the kernel instead of copying the entire kernel (outlined below in appendix)). Keep hitting "exit" until you're prompted to save changes, choose "yes".

Once you have it configured, start building. This usually takes a few minutes.

make && make modules

The new kernel will be at "arch/arm/boot" in a compressed format called "zImage". The uncompressed version is simply called "Image". With the default partitioning scheme it is REQUIRED that the kernel be < 2096640 bytes in size. If you need to shorten the size, try including your changes to the kernel as modules instead. Otherwise you will need to resize the kernel partition to account for the size difference.

Now that you have a kernel you can install it as you would our stock. See the #Backup / Restore section for examples on writing this to disk.

Now we need to install the modules.

mkdir newmodules
INSTALL_MOD_PATH=newmodules make modules_install
 
#Replace /dev/sdb with your sd card
mkdir /mnt/miniSD4
mount /dev/sdb4 /mnt/miniSD4/
 
#Remove existing modules:
rm -r /mnt/miniSD4/lib/modules/*
cp -r newmodules/* /mnt/miniSD4/
 
umount /mnt/miniSD4

After you install the new modules, you will need to boot the kernel and run "depmod -a" to rebuild the dependency map. You can them use modprobe to load the individual modules.

You can also copy individual modules to your existing kernel assuming the kernel is the exact same version as the installed one.

If you require functionality from a newer kernel, we also provide sources for the 2.6.36 kernel patched with support as-is. You can find the sources here. You will need to also use this toolchain. The rest of the steps for building the kernel are the same. This kernel should function the same as the other, however the USB device driver is not implemented. We strongly suggest using the 2.6.24 kernel unless you have a requirement for a later kernel as the 2.6.24 is supported and has gone through much more testing through various productions.

We also now have a copy of a 3.4.0 kernel source here. These same instructions are applicable but you will need to use this toolchain instead of the one used with 2.6.24.

6 Features

6.1 CPU

This board features a CNS2132 250MHz ARM9 processor. For more details see the CPU Datasheet.

6.2 FPGA

This board features a Lattice LFXP2 FPGA. The CPU connects to the FPGA using SPI, and since access to SPI is not atomic we have implemented the SBUS as a safe way for multiple processes to access FPGA registers.

6.2.1 FPGA Bitstreams

The FPGA has the capability to be reloaded on startup and reprogram itself with different configurations. The default bitstream is hardcoded into the FPGA, but the soft reloaded bitstreams can be placed in /ts7500_bitstream.vme.gz on the initrd root to make the board load the bitstream on startup. You can also load the bitstream manually using ts7500ctl:

ts7500ctl --loadfpga bitstream.vme
# or
ts7500ctl --loadfpga bitstream.vme.gz

A list of our pre-built bitstreams can be found on our FTP site

If we do not have a configuration you need, you can build a new bitstream, or contact us for our engineering services.

Bitstream Revision SD controller SPI XNAND CAN XUARTs
Default 5 On On On Off 0-7

The released FPGA has undergone minor bug fixes throughout the product liftime.

FPGA Revision Log
Revision Changes
0 Initial Release
1 Added 5-bit PLL phase shift register for SPI to increase temperature margin.
2 * Improved GPIO performance by putting the syscon block on its own clock domain synchronous to the SPI clock.
  • SPI controller updates.
3 Corrected XUART0 RX line
4 * Added improved SPI controller and extra CS2# and CS3#
 * Optional CAN controller added
 * Fixed IRQ output
5 * Updated SPI controller with extra slower speeds (1.2Mhz) and CS# bit in control reg.
 * USB Device fixes
6 CAN Fixes

6.2.2 FPGA Programming

Note: We do not provide support for the opencores under our free support, however we do offer custom FPGA programming services. If interested, please contact us.

The opencore FPGA sources are available here.

We have prepared the opencore projects which gives you the ability to reprogram the FPGA while either preserving or removing our functionality as you choose. The code sources are in verilog, and we use Lattice Diamond to generate the JEDEC file. You can download Lattice Diamond from their site. You can request a free license, and it will run in either Windows or Linux (only Redhat is supported). In the sources you can find the functionality switches in the <boardname>_top.v file:

parameter sdcard_opt = 1'b1;
parameter spi_opt = 1'b1;
parameter nandflash_opt = 1'b1;
parameter can_opt = 1'b1; /*If CAN is enabled, only two XUARTs can be used*/
/* software currently requires these to be enabled/disabled contiguously. */
parameter xuart0_opt = 1'b1;
parameter xuart1_opt = 1'b1;
parameter xuart2_opt = 1'b0;
parameter xuart3_opt = 1'b0;
parameter xuart4_opt = 1'b0;
parameter xuart5_opt = 1'b0;
parameter xuart6_opt = 1'b0;
parameter xuart7_opt = 1'b0;

You can use these switches to enable and disable functionality. We do not enable everything at the same time because of space constraints on the FPGA. So for example, to disable CAN and enable the rest of the XUARTS:

parameter sdcard_opt = 1'b1;
parameter spi_opt = 1'b1;
parameter nandflash_opt = 1'b1;
parameter can_opt = 1'b0; /*If CAN is enabled, only two XUARTs can be used*/
/* software currently requires these to be enabled/disabled contiguously. */
parameter xuart0_opt = 1'b1;
parameter xuart1_opt = 1'b1;
parameter xuart2_opt = 1'b1;
parameter xuart3_opt = 1'b1;
parameter xuart4_opt = 1'b1;
parameter xuart5_opt = 1'b1;
parameter xuart6_opt = 1'b1;
parameter xuart7_opt = 1'b1;

For more advanced changes you may look to opencores.org which has many examples of FPGA cores. To build the FPGA with your new changes, go to the 'Processes' tab and double-click 'JEDEC File'. This will build a jedec file in the project directory. On a linux system, either x86 compatible or ARM, we provide an application called jed2vme.

jed2vme for x86

jed2vme for ARM (oabi)

We also have the sources here.

WARNING: Do not use the 'jed2vme' provided by Lattice. Their version writes to flash and as the opencores do not contain the bootrom so this will brick your board.

jed2vme can be used like this:

jed2vme bitstream.jed | gzip > bitstream.vme.gz

To execute this on your board run this:

ts7500ctl --loadfpga=bitstream.vme
# or
ts7500ctl --loadfpga=bitstream.vme.gz

As space is constrained in the initrd it is suggested to gzip the file as shown in the jed2vme example. To load this bitstream automatically you can place it in the root of the initrd and name it '/ts7500_bitstream.vme.gz'. The linuxrc script will by default load this bitstream immediately on startup (before the fastboot shell). You should first test it manually to make sure it loads ok.

The FPGA contains flash memory which contains Technologic System's default FPGA flash load. Using an SRAM bitstream generated by our "jed2vme" with "ts7500ctl --loadfpga" will not overwrite the flash memory of the FPGA and will only load the SRAM contents of the FPGA, making for an unbrickable system.

6.3 XUARTs

The XUART controller is a core we have included in the FPGA, as well as a userspace application called xuartctl for accessing these UARTs. Rather than using a kernel driver with the standard serial interface, we have implemented the XUARTs with features to simplify application development. The XUARTs allow you to easily use arbitrary baud rates, nonstandard modes such as DMX or 9n1, and they allow a very low latency operation. The XUART layer also uses the very low overhead TCP layer which allows you to transport serial over the network without writing any code.

The simplest example to get started is to define the port with:

xuartctl --server --port=1 --speed=115200

This will return "ttyname=/dev/pts/0", or a higher pts number. You can use this /dev/pts/# device to access the UART, but note that the pts device number can change based on other ssh, telnet or other processes. See this section for a sample script to setup the XUARTs with a predictable device name.

For more information and detailed usage, see the xuartctl page.

The XUARTs like many other standard UARTs poll the RX buffers by default. The XUARTs have large RX FIFOs so polling at 100hz is the best choice for many applications. At the expense of more CPU time you can use an IRQ to achieve a much lower latency. This board uses IRQ 29 for the XUART IRQ. You can edit the linuxrc script and change the xuartctl server to start with:

xuartctl --irq=29 --server

6.4 Battery powered RTC

The RTC connects through I2C to the FPGA. Typically, the battery-backed real time clock is only set or read in the linuxrc bootup script by the ts7500ctl utility. It is only necessary to read the RTC once per bootup to initialize the Linux time of day. This is done with the command "ts7500ctl --getrtc". To set the RTC time, you simply set the Linux time of day (with e.g. the "date" utility) and then run ts7500ctl --setrtc. RTC's are already set before shipment to atomic UTC time and should hold time within 15 PPM while at room temperature.

WARNING: Be careful when handling board with a battery inserted -- the battery holder leads are through-hole and should the board be placed on a conductive surface and short the battery leads, the RTC will loose its track of time and need to be reset.

6.5 COM Ports

The XUART ports will be controlled with xuartctl. By default they will not have devices in /dev/.

Name Type Location
ttyS0 (console) TTL pins 7 (TX) and 8 (RX) of the #44 Pin Header.
XUART0 TTL pins 5 (TX) and 6 (RX) of the #44 Pin Header.
XUART1 TTL pins 19 (TX), 20 (RX), and 27 (TXEN) of the #44 Pin Header.
XUART2 TTL pins 21 (TX), 22 (RX), and 28 (TXEN) of the #44 Pin Header.
XUART3 TTL pins 23 (TX) and 24 (RX) of the #44 Pin Header.
XUART4 TTL pins 25 (TX) and 26 (RX) of the #44 Pin Header.
XUART5 TTL pins 31 (TX), 32 (RX), and 29 (TXEN) of the #44 Pin Header.
XUART6 TTL pins 34 (TX), 33 (RX), and 30 (TXEN) of the #44 Pin Header.
XUART7 TTL pins 36 (TX) and 35 (RX) of the #44 Pin Header.

6.6 SD

This product contains our SD controller implemented in the FPGA. This will support both SD and SDHC cards, sizes up to 32GB are supported. The SD card access is implemented in userspace by acting as an NBD server. The sdctl page which will show more advanced usage and the linuxrc script will bring up the nbd-clients in this layout:

 /dev/nbd5 - whole disk device of microSD card
 /dev/nbd6 - 1st partition of SD card (Windows VFAT filesystem on devkit card)
 /dev/nbd7 - 2nd partition of SD card (kernel partition on devkit card)
 /dev/nbd8 - 3rd partition of SD card (EXT2 initrd partition on devkit card)
 /dev/nbd9 - 4th partition of SD card (Debian EXT3 filesystem on devkit card)
Note: NBD devices report their size as SIZE_MAX for more flexibility when using them with sdctl. If you are formatting a partition or using dd you will need to specify the size of the block device or partition.

6.7 SPI Flash

The SPI flash is also implemented in userspace with NBD, however it is not mounted or running by default. Even when you are booted to SPI, it does not need to access it directly since the bootrom will load it into memory before the Linux kernel is even executing. If you want to mount any part of it see the spiflashctl page for usage.

6.8 CAN

Note: The default TS-7500 bitstream does not include CAN. See the #FPGA Bitstreams section for more information on bitstreams including CAN.

The FPGA contains a SJA1000C compatible CAN controller that can be accessed using canctl which provides a CAN network service. Any application on the network can make use of this service to send or receive CAN packets using the API defined by canctl. Thus, it is possible to develop code written in other languages (java, python, etc.) and/or to run this code under other operating systems.

The canctl server is started by running:

Note: Due to a bug in some releases, daqctl will grab the IRQ before canctl. If CAN is unable to take the IRQ you can stop the daqctl process to reclaim it:
killall daqctl
canctl --server

The easiest interface to CAN is calling "canctl" through the command line:

canctl --port=127.0.0.1 --txdat=01:02:03:04:05:06
# canctl --help
Technologic Systems CAN controller manipulation.
-a | --address=ADR        CAN register address
-b | --baud=BAUD          CAN baud rate (7500 to 1000000)
-R | --peek8r             CAN register read
-W | --poke8w=VAL         CAN register write
-i | --txid=ID            CAN TX packet ID
-T | --txrtr              TX RTR packet
-d | --txdat=DAT          TX packet with data DAT
-s | --server==<port>     Daemonize and run as server
-D | --dump               Receive and print all CAN packets
-0 | --btr0=BTR0          SJA1000 BTR0 bus timing reg val
-1 | --btr1=BTR1          SJA1000 BTR1 bus timing reg val
-t | --txtest             Send TX test pattern
-r | --rxtest             Do RX test
-p | --port=<host><:port> Talk to canctl server
-S | --std                Send standard frame (not extended)
-v | --recover            Automatically recover from bus-off

The canctl application implements network CAN functionality using the can_rx_remote() and can_tx_remote() functions. These functions which read and write one fixed-size packet of struct canmsg to a TCP socket descriptor. Writing your own canctl client in the language of your choice is as simple as doing the same thing. The format of the each CAN packet sent or received via the network interface is described below. The terms "Rx" and "Tx" are relative to the client, so "Rx" would describe packets read from CAN over the network and "Tx" would describe packets written to CAN over the network.


 UINT32   flags:
          bit 7 - set on Tx if packet is a control packet
                  control packets are intercepted by the
                  canctl server to allow control functionality.
          bit 6 - set if message originates locally (unused)
          bit 5 - set if CAN message has extended ID
          bit 4 - set if remote transmission request (RTR)
          bit 3 - set on Rx if CAN error warning condition occurred
          bit 2 - set on Rx if CAN bus had a data overrun
          bit 1 - set on Rx if CAN bus went error passive
          bit 0 - set on Rx if a CAN bus error occurred
          Error conditions are reported for informational
          purposes.  The server normally handles these errors
          and recovers from them.
              control information present (reserved for future use)
              message originates from this node (unused)
 UINT32   CAN id
 UINT32   timestamp_seconds
 UINT32   timestamp_microseconds
 UINT32   bytes of CAN data which are valid
          if bit 7 of flags is set, this byte is instead interpreted
          as a command number:
            0 = set acceptance filter
              if the acceptance filter has been set, then only
              CAN packets which pass the filter will be received.
              to pass the filter, all bits in the acceptance filter
              which are to be checked (specified by a 1 in the
              corresponding bit of the mask) are compared (filter
              id compared to corresponding bit in received id).
              only if all bits to be checked do match will the
              packet be received.
 UINT8[8] CAN data
          if bit 7 of flags is set, this byte is instead interpreted
          as follows:
            cmd 0:
              UINT32 acceptance filter id
              UINT32 acceptance filter mask

UINT32 values are sent in little-endian format.

So for example, to send a standard CAN packet of length 6 with contents 01:02:03:04:05:06 and CAN id 55 it would be necessary to open a TCP connection to port 7552 on the device with the canctl server running, and the write the following packet to the socket:

  00 00 00 00 55 00 00 00 00 00 00 00 00 00 00 00 06 00 00 00 01 02 03 04 05 06 00 00

6.9 Syscon

The Syscon is an FPGA core that presents various configuration registers for the board. These registers are accessed through the SBUS. For example, to read the "Model ID" register:

ts7500ctl --address=0x60 --peek16

See the SBUS page for more details on using the SBUS in your application.

Offset Bits Access Function
0x60 15-0 Read Only Model ID
0x62 15 Read/Write Green LED (1 = on)
14 Read/Write Red LED (1 = on)
13 Read/Write RTC SCL input
12 Read/Write RTC SDA input
11 Read/Write RTC SCL direction (1 - output)
10 Read/Write RTC SDA direction (1 - output)
9 Read/Write RTC SCL output
8 Read/Write RTC SDA output
7-4 Read Only Board submodel
3-0 Read Only FPGA revision
0x64 15-0 Read Only 16-bits of random data changed every 1 second.
0x66 15-12 Read Only DIO input for pins 40(MSB)-37(LSB)
11-8 Read/Write DIO output for pins 40(MSB)-37(LSB)
7-4 Read/Write DIO direction for pins 40(MSB)-37(LSB) (1 - output)
3 Read/Write Lattice tagmem clock
2 Read/Write Lattice tagmem serial-in (RW)
1 Read/Write Lattice tagmem CSn
0 Read Only Lattice tagmem serial-out (RO)
0x68 15-0 Read Only DIO input for pins 36(MSB)-21(LSB)
0x6a 15-0 Read Only DIO output for pins 36(MSB)-21(LSB)
0x6c 15-0 Read/Write DIO direction for pins 36(MSB)-21(LSB) (1 - output)
0x6e 15-0 Read/Write DIO input for pins 20(MSB)-5(LSB)
0x70 15-0 Read/Write DIO output for pins 20(MSB)-5(LSB)
0x72 15-0 Read/Write DIO direction for pins 20(MSB)-5(LSB) (1 - output)
0x74 15-0 Write Only #Watchdog feed register
0x76 15-11 N/A Reserved
10-6 Read/Write PLL phase (set by TS-BOOTROM)
5 Read Only mode3 latched bootstrap bit
4 Read/Write Reset switch enable (1 - auto reboot when dio_i[9] == 0)
3-2 Read/Write scratch reg
1 Read Only mode2 latched bootstrap bit
0 Read Only mode1 latched bootstrap bit

6.10 Watchdog

By default the watchdog is fed by ts7500ctl. This way if userspace, the kernel, or the FPGA communication has any issue the board will reboot. For many applications this may be enough, but you can tailor this more specifically to your application by feeding the watchdog on your own criteria. The watchdog feed register is write-only. Valid write values are:

Value Result
0 feed watchdog for another .338s
1 feed watchdog for another 2.706s
2 feed watchdog for another 10.824s
3 disable watchdog

Watchdog by default comes out of reset armed for .338 seconds. TS-BOOTROM firmware feeds for 10.824 and OS code has 10.824 seconds to take over. If you would like to run your own watchdog you will need to kill ts7500ctl when switching to your own application. You can feed the watchdog from your application by poking a register:

// Compile with gcc filename.c -o watchdog
#include <stdio.h>
#include <unistd.h>
#include "sbus.h"
 
int main(int argc, char **argv)
{
        // This is an example of feeding the watchdog for 10s
        for (;;) 
        {
                sbuslock();
                sbus_poke16(0x74, 2);
                sbusunlock();
                sleep(5); // Sleeping half of the 
                          // feeding time is usually a safe value
        }
 
        return 0;
}

6.11 DIO

This board brings out only FPGA DIO. Since the FPGA is connected to the processor using SPI which is not atomic, we have created the SBUS which allows safe access from multiple processes. The SBUS mechanism of locking as well as it being a serial bus to the FPGA does put a limit on how fast the DIO can be read or set. Depending on the needs of the application the code can be structured to provide a bit of flexibility in speeds.

The "ts7500.subr" file provides the simplest method for accessing these DIO, but not the fastest:

# If you're in the initrd:
source /ts7500.subr
 
# If you're in Debian:
source /initrd/ts7500.subr
 
#Usage: setdiopin <pin> <1,0,Z> <b>
setdiopin 20 0
 
#Usage: getdiopin <pin>
getdiopin 21

You can also interface with this DIO in C using the example here.

...
sbuslock();
setdiopin(21, (getdiopin(21) ^ 0x01));
sbusunlock();
...

Using this method of an atomic read-modify-write will achieve about a 20KHz wave with a 50% duty cycle.

...
sbuslock();
setdiopin(21, 1);
setdiopin(21, 0);
sbusunlock();
...

Using this method of atomic writes will achieve about a 30KHz wave with about a 20% duty cycle.

The SBUS link between the FPGA and CPU is SPI with a 16-bit data frame per bus cycle. When setting and reading one pin at a time, a whole 16-bit cycle is used to accomplish the needed goal. If multiple pins need to be set or read at once, a performance gain can be had from reading/writing entire 16bit registers at a time as opposed to iterating through each pin sequentially.

Other factors can contribute to speeds of the SBUS. Since the SBUS is shared across multiple peripherals there could be bus contention. It may also be that there are very few other applications wanting access to the bus, it all depends on usage. There is more overhead in doing a sbuslock() and sbusunlock() after every transaction than there would be to queue up transactions, lock the bus, and then do them all at once. There is also another function provided in sbus.c that is a smarter version of sbusunlock(), it is called sbuspreempt(). sbuspreempt() will check to see if any other applications are blocked in acquiring the lock, if there are, the SBUS is unlocked, giving other applications access to it. If there are no other applications waiting for the lock, the current application retains the lock. The benefit of this, is next time sbuslock() is called, the function returns almost instantly because the lock is already held. This greatly reduces overhead.

It may be necessary to "tune" an application with locking, unlocking, and preempting the SBUS to find what works best if speed is a factor.

The DIO registers are described in the #Syscon section. This board has 40 logical DIO registers on the FPGA to remain consistant with the series, but not all of the pins are brought out. DIO 9 by default is an external reset which is pulled high, and when it is set to 0 the board will reboot. You can disable this functionality by clearing bit 4 of 0x76 in the #Syscon.

DIO Number Location Alternate Function
5 Pin 5 of the #44 Pin Header MODE2, XUART 0 TX
6 Pin 6 of the #44 Pin Header XUART 0 RX
7 Pin 7 of the #44 Pin Header MODE1
8 Pin 8 of the #44 Pin Header N/A
9 Pin 9 of the #44 Pin Header Reset (default)
11 Pin 11 of the #44 Pin Header SPI CS#
12 Pin 12 of the #44 Pin Header SPI MISO
13 Pin 13 of the #44 Pin Header SPI MOSI
14 Pin 14 of the #44 Pin Header SPI CLK
19 Pin 19 of the #44 Pin Header XUART 1 TX
20 Pin 20 of the #44 Pin Header XUART 1 RX
21 Pin 21 of the #44 Pin Header XUART 2 TX
22 Pin 22 of the #44 Pin Header XUART 2 RX
23 Pin 23 of the #44 Pin Header XUART 3 TX, CAN TX
24 Pin 24 of the #44 Pin Header XUART 3 RX
25 Pin 25 of the #44 Pin Header XUART 4 TX
26 Pin 26 of the #44 Pin Header XUART 4 RX
27 Pin 27 of the #44 Pin Header XUART 1 TXEN
28 Pin 28 of the #44 Pin Header XUART 2 TXEN
29 Pin 29 of the #44 Pin Header XUART 5 TXEN
30 Pin 30 of the #44 Pin Header XUART 6 TXEN
31 Pin 31 of the #44 Pin Header XUART 5 TX
32 Pin 32 of the #44 Pin Header XUART 5 RX
33 Pin 33 of the #44 Pin Header XUART 6 TX
34 Pin 34 of the #44 Pin Header XUART 6 RX
35 Pin 35 of the #44 Pin Header XUART 7 TX
36 Pin 36 of the #44 Pin Header XUART 7 RX
37 Pin 37 of the #44 Pin Header N/A
38 Pin 38 of the #44 Pin Header N/A
39 Pin 39 of the #44 Pin Header N/A
40 Pin 40 of the #44 Pin Header N/A

6.12 Random Number Generator

The FPGA has a random number generator. On startup, ts7500ctl is called with the --setrng option to seed Linux's random number generator from the hardware random number generator. Without a good source of entropy, Linux's random number generator will start up in a very predictable state which is undesirable for the security of many cryptography protocols.

6.13 Interrupts

This board does not bring out any CPU DIO directly, so to access any IRQs you would require an FPGA customization. There are 2 IRQs connected to the FPGA which are typically used for CAN or the XUART core. The XUARTs by default will poll at 100hz which will be acceptable for most applications accessing the UARTs so this IRQ may not be required. See the #FPGA Programming section for more details.

We include a userspace IRQ patch in our kernels. This allows you to receive interrupts from your applications where you would normally have to write a kernel driver. This works by creating a file for each interrupt in '/proc/irq/<irqnum>/irq'. The new irq file allows you to block on a read on the file until an interrupt fires.

The original patch is documented here.

This example below will work with any of our TS-Socket boards running Linux. This opens the IRQ number specified in the first argument and prints when it detects an IRQ.

#include <stdio.h>
#include <fcntl.h>
#include <sys/select.h>
#include <sys/stat.h>
#include <unistd.h>
 
int main(int argc, char **argv)
{
	char proc_irq[32];
	int ret, irqfd = 0;
	int buf; // Holds irq junk data
	fd_set fds;
 
	if(argc < 2) {
		printf("Usage: %s <irq number>\n", argv[0]);
		return 1;
	}
 
	snprintf(proc_irq, sizeof(proc_irq), "/proc/irq/%d/irq", atoi(argv[1]));
	irqfd = open(proc_irq, O_RDONLY| O_NONBLOCK, S_IREAD);
 
	if(irqfd == -1) {
		printf("Could not open IRQ %s\n", argv[1]);
		return 1;
	}
 
	while(1) {
		FD_SET(irqfd, &fds); //add the fd to the set
		// See if the IRQ has any data available to read
		ret = select(irqfd + 1, &fds, NULL, NULL, NULL);
 
		if(FD_ISSET(irqfd, &fds))
		{
			FD_CLR(irqfd, &fds);  //Remove the filedes from set
			printf("IRQ detected\n");
 
			// Clear the junk data in the IRQ file
			read(irqfd, &buf, sizeof(buf));
		}
 
		//Sleep, or do any other processing here
		usleep(10000);
	}
 
	return 0;
}

6.14 I2C

The I2C_SCL and I2C_SDA pins bring out the I2C bus from the CNS2132 CPU. We do have an example for connecting to the I2C bus that uses the temperature sensor used on some of this series. You can find the C example here.

Please refer to the CNS2132 user's guide, page 55, 144, and 312 for more information on this I2C bus.

6.15 SPI

This core is for high speed SPI with auto-CS#. Starts at offset 0x40 on the this series. Chip select #0 is typically used for onboard spiflash. Chip select #1 is used for offboard spiflash. The last 2 chip selects are always available on the Cavium series boards.

The SPI controller is an FPGA core which is accessed using spictl. The simplest method for communication is calling spictl through bash:

# Read 32 bytes from LUN1
spictl --lun=1 --readstream=32
 
# Write Hello (68:65:6c:6c:6f)
spictl --lun=1 --writestream=68:65:6c:6c:6f

Usage:

ts7500:~# spictl --help
Technologic Systems SPI controller manipulation.

General options:
-c | --clock=frequency    SPI clock frequency
-e | --edge=value         set clock edge (positive for > 0, negative for < 0)
-w | --writestream=data   write colon delimited hex octets to SPI
-d | --readwrite=data     write colon delimited hex octets to SPI while reading to stdout
-r | --readstream=bytes   read specified number of bytes from SPI to stdout
-o | --holdcs             don't de-assert CS# when done
-l | --lun=id             Talk to specified chip number
-s | --server=<port>      Daemonize and run as server listening on port
-p | --port=<host><:port> Talk to spictl server
hex octets are hexadecimal bytes. for example,
this command reads 32 bytes of CS#1 SPI flash from address 8192:
./spictl -l 1 -w 0B:00:20:00:00 -r 32

The spictl utility can also run as a TCP server which lets you easily access SPI in your application. To start the tcp server on port 7755:

spictl --server=7755

The data stream packet to a spictl server consists of opcodes and operands. Each opcode is one byte long and may encode part or all of the operand. Some opcodes specify that additional bytes of data follow to contain the remainder of the operands.

There are four opcodes encoded in the two msb of the opcode byte:

  • OPCODE 0 = CHIP SELECT
    • The chip number is encoded in the two LSB.
      • 00 = CS#0
      • 01 = CS#1
      • 10 = CS#2
      • 11 = CS#3
    • If Bit 5 is set, OPCODE = ASSERT CHIP SELECT.
    • Then If Bit 3 is set, Bit 2 is the new SPI edge to use (1 = positive edge, 0 = negative edge). Also, two additional bytes follow as operands. These two bytes are a big-endian encoded clock value. This value multiplied by 2048 is the SPI clock frequency to use. If Bit 5 is clear, OPCODE = DE-ASSERT CHIP SELECT
  • OPCODE 1 = READ
    • The number of bytes to read must be a power of two, encoded in the 6 lsb. These six bits represent the number to raise 2 to the power of to get the length. So,
      • 00_0000 = 1 byte
      • 00_0001 = 2 bytes
      • ...
      • 00_1100 = 4096 bytes
  • OPCODE 2 = WRITE
    • The number of bytes to write is encoded in the same manner as for a READ opcode. After the opcode byte, the number of bytes to write follows as the operands.
  • OPCODE 3 = READWRITE
    • This opcode encodes identically as the WRITE opcode. However it specifies that bytes are to be READ as well as written.

You can also use the spictl --server=<port> and run a second invokation of spictl with --port=<port> to have the second instance act as a client to the server. You can then use tcpdump to see the exact tcp packets being sent back and forth for various operations.

The table below is the register map for the SPI in the FPGA:

Offset Access Bit(s) Description
0x40 Read Only 15 SPI MISO state
Read/Write 14 SPI CLK state
Read/Write 13:10 Speed - 0 (highest), 1 (1/2 speed), 2 (1/4 speed)...
Read/Write 9:8 LUN (0-3 representing the 4 chip selects)
Read/Write 7 CS (1 - CS# is asserted)
N/A 6:1 Reserved
Read/Write 0 Speed
0x42 Read Only 15:0 Previous SPI read data from last write
0x44 N/A 15:0 Reserved
0x46 N/A 15:0 Reserved
0x48 Read/Write 15:0 SPI read/write with CS# to stay asserted
0x4a Read Only 15:0 SPI pipelined read with CS# to stay asserted
0x4c Read/Write 15:0 SPI Read/Write with CS# to deassert post-op
0x4e N/A 15:0 Reserved

The SPI clk state register should be set when CS# is deasserted. Value 0 makes SPI rising edge (CPOL=0), 1 is falling edge (CPOL=1). This only applies to speed >= 1. For speed == 0, SPI clock polarity/skew must be set from the PLL phase adjust registers in the syscon block.

Where the base clock is 75Mhz (extended temp alters this to 50Mhz), speed settings break down as follows:

 0 - 75Mhz (/1)
 1 - 37.5Mhz (/2)
 2 - 18.75Mhz (/4)
 3 - 12.5Mhz (/6)
 4 - 9.375Mhz (/8)
 5 - 7.5Mhz (/10)
 6 - 6.25Mhz (/12)
 7 - 5.36Mhz (/14)
 8 - 4.68Mhz (/16)
 9 - 4.17Mhz (/18)
 ...
 15 - 2.5Mhz (/30)
 ... 
 19 - 1.97MHz (/38)
 ...
 31 - 1.21MHz (/62)

Bits 10-15 were not present on TS-75XX FPGA prior to rev 4. On those TS-75XX's, SPI speed was hardcoded to 75Mhz and 75Mhz only.

The pipelined read register is for read bursts and will automatically start a subsequent SPI read upon completion of the requested SPI read. Reading from this register infers that another read will shortly follow and allows this SPI controller "a head start" on the next read for optimum read performance. This register should be accessed as long as there will be at least one more SPI read with CS# asserted to take place. This register is an appropriate target address for SBUS burst reads.

The SPI pins on the TS-7500 are available on the #44 Pin Header. DIO_11 is CS1, DIO_37 is CS2, and DIO_39 is CS3.

6.16 External Reset

Driving the external reset pin (DIO 9) low will reset the CPU by default. You can disable this functionality by running:

ts7500ctl --resetswitchoff

6.17 Temperature Sensor

The TS-752 baseboard has a temperature sensor, which the TS-7500 and TS-7550 speak to via SPI. Information on how this is done is contained in the ts7500.subr script thus:

gettemp() {
# Determine the board model
# If 7500 or 7550, use local function
# For all other boards, use "ts7500ctl --gettemp"
local model=`ts7500ctl -i | grep "^model=" | cut -d= -f2 | cut -c3-`
if [ "$model" -ne 7500 -a $model -ne 7550 ]; then
        eval `ts7500ctl --gettemp`
        echo $temperature
        return
fi
 
        local n x val
        setdiopin 22 0
        setdiopin 12 Z
        n=0
        while [ $n -lt 13 ]; do
                setdiopin 14 0
                setdiopin 14 1
                x=`getdiopin 12`
                if [ "$x" -eq 0 ]; then
                        let val="val << 1"
                else
                        let val="(val << 1) | 1"
                fi
                let n="n + 1"
        done
        setdiopin 22 Z
        setdiopin 14 Z
        if [ $((val & 0x1000)) -ne 0 ]; then
                val=$(((~(val & 0xfff) & 0xfff) + 1))
                val=$((val * 62500))
                printf "-%d." $((val / 1000000))
                printf "%d\n" $(((val % 1000000) / 100000))
        else
                val=$((val * 62500))
                printf "%d." $((val / 1000000))
                printf "%d\n" $(((val % 1000000) / 100000))
        fi
 
        return $val
}

7 External Interfaces

7.1 44 Pin Header

The 44 pin header contains almost all of the I/O on the TS-7500. On the baseboard, typically the 4 JTAG pins are left hanging:

TS-7500-TS-752-40pins.jpg

The CN-PC104-40PIN-F is available as a mating connector to this header.

Pin # Schematic Name Maximum Voltage DIO Default State Function
1 JTAG_DOUT N/A N/A Used for factory programming
2 JTAG_TMS N/A N/A Used for factory programming
3 JTAG_CLK N/A N/A Used for factory programming
4 JTAG_DIN N/A N/A Used for factory programming
5 DIO_05 / MODE2 3.3V Pulled high Used to toggle boot device / XUART0_TX
6 DIO_06 3.3V Pulled high XUART0_RX
7 DIO_07 3.3V Pulled high Console TX / MODE1
8 DIO_08 3.3V Pulled high Console RX
9 DIO_09 3.3V Pulled high #RESET - ground to reset the board
10 3.3V 3.3V N/A Provides 3.3V
11 DIO_11 / SPI_CS# 3.3V Pulled high Chip select 1
12 DIO_12 3.3V Floating SPI_MISO
13 DIO_13 3.3V Pulled down SPI_MOSI
14 DIO_14 3.3V Pulled high SPI CLK
15 5V 5V N/A Provides 5V
16 GND N/A N/A Ground
17 SCL 3.3V Pulled high I2C SCL
18 SDA 3.3V Pulled high I2C SDA
19 DIO_19 3.3V Pulled high XUART1 TX
20 DIO_20 3.3V Pulled high XUART1 RX
21 DIO_21 3.3V Pulled high XUART2 TX
22 DIO_22 3.3V Pulled high XUART2 RX
23 DIO_23 3.3V Pulled high CAN TX / XUART3 TX
24 DIO_24 3.3V Pulled high CAN RX / XUART3 RX
25 DIO_25 3.3V Pulled high XUART4 TX
26 DIO_26 3.3V Pulled high XUART4 RX
27 DIO_27 3.3V Pulled high XUART1 TXEN
28 DIO_28 3.3V Pulled high XUART2 TXEN
29 DIO_29 3.3V Pulled high XUART5 TXEN
30 DIO_30 3.3V Pulled high XUART6 TXEN
31 DIO_31 3.3V Pulled high XUART5 TX
32 DIO_32 3.3V Pulled high XUART5 RX
33 DIO_33 3.3V Pulled high XUART6 TX
34 DIO_34 3.3V Pulled high XUART6 RX
35 DIO_35 3.3V Pulled high XUART7 TX
36 DIO_36 3.3V Pulled high XUART7 RX
37 DIO_37 3.3V Pulled high DIO 37
38 DIO_38 3.3V Pulled high DIO 38
39 DIO_39 3.3V Pulled high DIO 39
40 DIO_40 3.3V Pulled high DIO 40
41 POE_RX N/A N/A Power over ethernet
42 POE_78 N/A N/A Power over ethernet
43 POE_45 N/A N/A Power over ethernet
44 POE_TX N/A N/A Power over ethernet
Pin Layout
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
Note: Use of the JTAG pins for programming the board is not supported or recommended.

None of the DIO are tolerant to 5V. The FPGA DIO all support up to 3.3V with 12mA drive capability.

7.2 TS-752

See the TS-752 page for more information on the other available connectors.

7.3 COM Ports

The XUART ports will be controlled with xuartctl. By default they will not have devices in /dev/. Keep in mind these will be brought out in different locations when using a TS-752.

Name Type Location TX Enable
ttyS0 TTL pins 7 (TX) and 8 (RX) of the ##44 Pin Header. N/A
XUART0 TTL pins 5 (TX) and 6 (RX) of the #44 Pin Header. N/A
XUART1 TTL pins 19 (TX) and 20 (RX) of the #44 Pin Header. pin 27 of the #44 Pin Header
XUART2 TTL pins 21 (TX) and 22 (RX) of the #44 Pin Header pin 28 of the #44 Pin Header
XUART3 TTL pins 23 (TX) and 24 (RX) of the #44 Pin Header N/A
XUART4 TTL pin 25 (TX) and 26 (RX) on the #44 Pin Header N/A
XUART5 TTL pin 31 (TX) and 32 (RX) on the #44 Pin Header pin 29 of the #44 Pin Header
XUART6 TTL pin 34 (RX) and 33 (TX) on the #44 Pin Header pin 30 of the #44 Pin Header
XUART7 TTL pin 36 (RX) and 35 (TX on the #44 Pin Header N/A

8 Tips

8.1 SD Best Practices

Disk corruption is a common issue in embedded development and considerations must be made for a robust system. When used correctly, the Sandisk SD cards we include should provide a total write lifetime of around 8TB.

Counterfit cards, or bad media

It's been quoted from a Sandisk engineer that a third of the Sandisk branded flash cards on the planet are fake. We recommend Sandisk SD cards as that is what we use for our testing, but make sure you use a reputable source for acquiring any flash media.

We recommend avoiding ATP flash media as well as "Industrial SD cards". We have experienced corruption with Industrial Cards, though they seem to work if multiwrite is disabled but this makes the card extremely slow to write.

Interrupting a Write

Most issues are caused by interrupting a write to the storage media by disconnecting power. In a normal Linux environment for a server or desktop the start up and shutdown sequences should be very predictable, but on an embedded system a safe shutdown cannot always be guaranteed.

The most common issue is when powering off SD cards in the middle of a write. SD cards usually use MLC NAND flash for storage coupled with a manufacturer and model specific firmware. The NAND flash has a limitation where in order to perform a single byte write it must first read about 128KB to 256KB (or more) containing that byte into memory and erase that sector on the NAND chip. This is the erase block size and can vary based on the card. It takes the block in memory, changes the single byte in that copy, erases the intended location on the flash and then commits it back to the disk.

Most SD card firmwares also contain a wear leveling mechanism where they maintain a logical to physical mapping. This means that writing a contiguous file may actually end up in different areas in the NAND chip. If you interrupt a write cycle where it has erased a block, but not yet committed changes to the disk it will have lost data seemingly randomly across the card. There are several strategies you can adopt to avoid or limit your chance of corruption.

The most safe method is possible if you do not need to perform any writes that need to persist across reboots. If you are designing a data logger this is certainly not a good option, but if you're only responding to outside I/O this is your best choice. Once you get your application developed and ready for deployment you should try running from the initrd. This is already a read only filesystem which will never write to the disk. Powering off in the middle of a read is still safe. You can still write data to /tmp/ which will go to memory, but it will be lost on a poweroff. If you require the full Debian filesystem you could use the linuxrc-sdroot-readonly startup script. This will mount the Debian filesystem on the SD card as read only, but will commit any attempted writes to a ramdisk using unionFS. The downside to this configuration while booting to Debian is that you have to manage all writes to the system or risk filling up your memory and causing a crash.

The next best method is to use a battery backup. Most UPS backup solutions, or one you build yourself should contain a method to see the battery level. Once you reach lower levels you can simply run a "shutdown -h now". When power is available the board will boot back up, but you may want to check in the initrd while it is read only if the battery is back to an acceptable level before making the SD card read/write.

The last option is to limit your writes to reduce the chance of corruption. Make all of your writes to a ramdisk like /tmp/ and copy them to the physical media periodically or when you know power will be safe. This is the option many consumer electronics choose. You can make writes more predictable by mounting with the options "sync" which will stop linux from buffering writes in RAM, and "noatime" which will prevent linux from writing access times when reading a file.

If your application is losing power from users disconnecting it or powering it off you may want to consider using an LED to indicate when it is not safe to turn off. Most people have seen cameras or video games that say "Do not remove power while X is displaying" which is usually a graphic of a disk or an LED like on floppy drives to indicate that there is a write that should not be interrupted. You can implement this very simply with a system call:

     system("ts7500ctl --redledon");
     usleep(350000);
     int ret = write(...);
     system("ts7500ctl --redledoff");

The usleep allows the user time to react to a new write. Most people should be able to react to an LED in about 215ms, but to be safe I would use a higher number.

You may also want to consider using the XNAND which from our testing has proven to be much more reliable with sudden power loss.

Other Resources

8.2 Production Procedure

The stock boards contain a hook in the startup procedure that can be used to easily replicate an image from a thumb drive. The default linuxrc script will:

  • Check for a USB drive
  • Turn on red LED
  • If detected load USB and ethernet modules
  • Mount the first partition of the drive
  • Execute tsinit which should contain any blasting mechanism
  • Turn off red LED

To prepare the USB drive, erase any existing partitions and replace them with a single FAT32 or EXT2/EXT3 partition. The script will attempt to mount /dev/sda1. The linuxrc script will execute a file on the drive named "tsinit". Make sure the script is marked as executable.

This example expects an xnand-image.dd and/or an sd-image.dd in the root of the flash drive. If you exclude either, it will still run while only programming one. Normally, it will begin programming both and wait for them both to finish executing. When the script exits, the red LED will turn off automatically.

#!/bin/sh
 
# The linuxrc file will mount the USB drive in /mnt/usbdev/, so any
# files you access must use that path.
 
## Program Nand ##
killall nandctl
nandctl -XW 2048 -z 131072 -i /mnt/usbdev/xnand-image.dd &
 
## Program SD ##
dd if=/mnt/usbdev/sd-image.dd bs=32k conv=sync of=/dev/nbd5 &
 
## Program Onboard and Offboard SPI flash ##
spiflashctl -l 0 -W 64 -z 65536 -i /mnt/usbdev/spiflash-image.dd &
spiflashctl -l 1 -W 64 -z 65536 -i /mnt/usbdev/spiflash-image.dd &
 
wait

You could also mount a network drive and write the image from NFS rather than keeping the image on the USB drive.

9 Errata

9.1 Cavium PHY Ethernet Link Loss

Synopsis Link drop with certain cable lengths/switches on 100Mb/s networks
Severity Normal
Class Kernel Bug
Affected All TS-75XX/TS-4500 Boards
Status Workarounds available

Description:

The Cavium STR8100 integrated PHY in some circumstances can drop connection to the network. You can see this in dmesg as:

 star_nic_shutdown: stoping patch check.

The issue appears to correspond to the length of cable used as well as the network device connected to the board.

Workaround:

You can force the cavium PHY to 10MB/s which drastically improves reliability, and in most cases eliminates the issue. This needs to be run each time the interface is brought back up. If link is lost you would need to reset the interface (ifconfig eth0 up && ifconfig eth0 down) and run the devmem command again.

# From the initrd:
devmem 0x70000004 32 0x43075
 
# From Debian
busybox devmem 0x70000004 32 0x43075

This will disable the link speed auto-negotiation and force the PHY to communicate at 10Mb/s.

9.2 Ethernet driver can cause kernel delays

Synopsis 160ms Delay with ETH0 Disconnected
Severity Minor
Class Kernel Bug
Affected All TS-75XX/TS-4500 Boards
Status Workarounds available

Description:

The Cavium STR8100 NIC driver was programmed with 160ms delays when Ethernet is physically disconnected (see function static void internal_phy_patch_check(int init) of .../drivers/net/str8100/star_nic.c). This causes delayed responses in real-time applications such as canctl. When Ethernet is physically connected, the issue is nonexistent.

Workaround:

TS-75XX/TS-4500 users wanting to utilize real-time responses without Ethernet plugged in will need to either:

1. Bring the eth0 interface down with the command:

ifconfig eth0 down

2. Recompile the kernel without the Ethernet driver from Cavium (.../drivers/net/str8100/star_nic.c)

9.3 Incorrect DDR-RAM timing

Synopsis Incorrect DDR-RAM timing causing RAM corruption
Severity High
Class Hardware bug
Affected TS-7500 FPGA rev 0x04 and below

TS-7550 FPGA rev 0x03 and below

TS-7552 FPGA rev 0x02 and below

TS-7553 FPGA rev 0x00

TS-4500 FPGA rev 0x02 and below

Status Workarounds available

Description:

One of the RAM timing registers has a value that is not completely compatible with our hardware layout. This bug has the ability to manifest single bit-flips at various temperatures and yet work correctly in another temperature range. This can cause issues with USB read/write (due to heavy DMA use), system instability, or system hangs (which by default results in a reboot due to the WDT). You can query your FPGA revision with the following command:

ts7500ctl -i

Workaround:

The permanent fix is to send back your SBC to us for reprogramming. There is a way however to modify the RAM timing register once the SBC is booted up and operational. The command:

devmem 0x72000030 32 0x22

Will put the correct timing value in the timing register, however, this leaves the SBC vulnerable to this corruption until the command is issued.

10 Product Notes

10.1 FCC Advisory

This equipment generates, uses, and can radiate radio frequency energy and if not installed and used properly (that is, in strict accordance with the manufacturer's instructions), may cause interference to radio and television reception. It has been type tested and found to comply with the limits for a Class A digital device in accordance with the specifications in Part 15 of FCC Rules, which are designed to provide reasonable protection against such interference when operated in a commercial environment. Operation of this equipment in a residential area is likely to cause interference, in which case the owner will be required to correct the interference at his own expense.

If this equipment does cause interference, which can be determined by turning the unit on and off, the user is encouraged to try the following measures to correct the interference:

Reorient the receiving antenna. Relocate the unit with respect to the receiver. Plug the unit into a different outlet so that the unit and receiver are on different branch circuits. Ensure that mounting screws and connector attachment screws are tightly secured. Ensure that good quality, shielded, and grounded cables are used for all data communications. If necessary, the user should consult the dealer or an experienced radio/television technician for additional suggestions. The following booklets prepared by the Federal Communications Commission (FCC) may also prove helpful:

How to Identify and Resolve Radio-TV Interference Problems (Stock No. 004-000-000345-4) Interface Handbook (Stock No. 004-000-004505-7) These booklets may be purchased from the Superintendent of Documents, U.S. Government Printing Office, Washington, DC 20402.

10.2 Limited Warranty

Technologic Systems warrants this product to be free of defects in material and workmanship for a period of one year from date of purchase. During this warranty period Technologic Systems will repair or replace the defective unit in accordance with the following process:

A copy of the original invoice must be included when returning the defective unit to Technologic Systems, Inc. This limited warranty does not cover damages resulting from lightning or other power surges, misuse, abuse, abnormal conditions of operation, or attempts to alter or modify the function of the product.

This warranty is limited to the repair or replacement of the defective unit. In no event shall Technologic Systems be liable or responsible for any loss or damages, including but not limited to any lost profits, incidental or consequential damages, loss of business, or anticipatory profits arising from the use or inability to use this product.

Repairs made after the expiration of the warranty period are subject to a repair charge and the cost of return shipping. Please, contact Technologic Systems to arrange for any repair service and to obtain repair charge information.