Flashing¶

There are several ways to flash firmware images, depending on the image you can to flash.

DFU¶

SIMtrace 2 comes with a USB DFU bootloader pre-installed which allows to flash the application firmware over USB using the dfu-util utility.

To get dfu-util:

sudo apt-get install dfu-util

To flash the firmware:

sudo dfu-util --device 1d50:PID --cfg 1 --alt 1 --reset --download BOARD-APP-dfu.bin

PID is the USB product ID for the corresponding hardware platform:

• 60e3 for the SIMtrace 2 board
• 4004 for the sysmoQMOD board

BOARD is the name of the target board for which the firmware image has been built:

• simtrace for the SIMtrace 2 board
• qmod for the sysmoQMOD board

APP is the firmware application name as listed in the firmware section.

You can find pre-built images on the firmware section.

To prevent having to use sudo in order to use dfu-util on SIMtrace 2, grant access permission to the USB device to the current user:

# create osmocom group
sudo groupadd osmocom
# add current user to osmocom group (user needs to re-login for this change to take effect)
sudo adduser $USERNAME osmocom
# grant access permission to SIMtrace 2 for osmocom group
sudo tee -a /etc/udev/rules.d/10-osmocom.rules << EOF
# SIMtrace 2
SUBSYSTEM=="usb", ATTRS{idVendor}=="1d50", ATTR{idProduct}=="60e3",  MODE="0660", GROUP="osmocom" 
# sysmoQMOD
SUBSYSTEM=="usb", ATTRS{idVendor}=="1d50", ATTR{idProduct}=="4004",  MODE="0660", GROUP="osmocom" 
EOF
# reload udev rules
sudo udevadm control --reload-rules
sudo udevadm trigger

dfu-util should reset the board and use the DFU bootloader.
Try the command a second time if it did not work at first.
If this still does not work, power up the board while pressing the BOOTLOADER button.

If the USB DFU bootloader is missing, defective, or needs to be updated, use the JTAG or SAM-BA methods to flash the bootloader firmware.

SAMBA¶

The SAM3S micro-controller comes with an embedded bootloader called SAMBA, allowing to flash firmwares over USB.
The SAMBA bootloader can be used to flash the DFU bootloader.
To activate the SAMBA bootloader:

1. short the ERASE pin on the top of the board with the nearby 3V3 pin using a jumper
2. connect SIMtrace 2 over USB to power it up (no LED will light up)
3. using lsusb you should find the following entry:
   

   ID 03eb:6124 Atmel Corp. at91sam SAMBA bootloader
   

4. using journalctl -f ensure SIMtrace 2 has been recognized as USB ACM device:
   

   kernel: usb 2-2: new full-speed USB device number 4 using xhci_hcd
   kernel: usb 2-2: New USB device found, idVendor=03eb, idProduct=6124
   kernel: usb 2-2: New USB device strings: Mfr=0, Product=0, SerialNumber=0
   kernel: cdc_acm 2-2:1.0: ttyACM0: USB ACM device
   kernel: usbcore: registered new interface driver cdc_acm
   kernel: cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters
   

5. remove the jumper shorting ERASE to 3V3
6. install the bossac utility to flash using the SAMBA protocol
   

   sudo apt install bossac
   

7. flash the USB DFU firmware using bossac (note: erase ensures no main application remains so to force booting the USB DFU bootloader; boot=1 ensures the micro-controller will boot from the internal flash instead of the embedded bootloader next time it is powered up)
   

   sudo bossac --port /dev/ttyACM0 --erase --write ./bin/simtrace-dfu-flash.bin --verify --boot=1
   

8. to prevent using sudo, grant to current user the permission to access USB serial devices (e.g. /dev/ttyACM0). Note: this change only takes effect after re-logging-in
   

   sudo adduser $USERNAME dialout
   

Once the USB DFU bootloader is flashed, when re-pluging SIMtrace 2 over USB, you can flash the main application firmware using the DFU method.

JTAG¶

It is also possible to flash or debug SIMtrace 2 over JTAG using the ARM 20-pin JTAG header on the top of the board.

To flash the USB DFU firmware using JTAG:

1. install the JTAG utility openOCD
   

   sudo apt install openocd
   

2. flash the USB DFU bootloader firmware
   

   openocd --file interface/jlink.cfg --file target/at91sam3sXX.cfg --command "init" --command "halt" --command "flash write_bank 0 ./bin/simtrace-dfu-flash.bin 0" --command "at91sam3 gpnvm set 1" --command "reset" --command "shutdown" 
   

   • replace interface/jlink.cfg with the configuration file for your JTAG debugging adapter
   • at91sam3 gpnvm set 1 ensures the micro-controller will boot from the internal flash (i.e. not from the embedded SAMBA bootloader)

The SAM3S also offers the low pin-count SWD alternative to JTAG, allowing to use an inexpensive ST-Link V2 (clone) to flash (and debug):

openocd --file interface/stlink-v2.cfg --command "set CPUTAPID 0x2ba01477" --file target/at91sam3sXX.cfg --command "init" --command "halt" --command "flash write_bank 0 ./bin/simtrace-dfu-flash.bin 0" --command "at91sam3 gpnvm set 1" --command "reset" --command "shutdown" 

SWD pinout:

Once the USB DFU bootloader is flashed, when re-pluging SIMtrace 2 over USB, you can flash the main application firmware using the DFU method.