TinyG2

This is the Other Machine Co production fork of Synthetos's g2 firmware.

Toolchain

This project requires gcc 4.8.

You can install the toolchain using any of the following commands:

make
make toolchain
cd Tools && make

Compiling Firmware

The firmware is contained in the TinyG2/ directory.

When compiling the TinyG firmware, you need to specify a platform:

make PLATFORM=Othermill
make PLATFORM=OthermillPro
make PLATFORM=G2v9i

You must build the firmware from the TinyG2/ directory:

cd TinyG2 && make PLATFORM=OthermillPro
cd TinyG2 && make PLATFORM=G2v9i

Alternatively, you can use the top-level Makefile shim:

make fw

This command build the G2v9i version of firmware, which is targeted for boards in V2 machines.

Firmware Binaries

Firmware binaries can be found in the TinyG2/bin folder. Output is organized by PLATFORM.

The build puts both an ELF and a binary. ELF is the executable linker format and has symbols for debugging. The .bin is the binary image that we supply to BOSSA.

Clean Build

To clean, run make clean at the top-level. By default, this will run a clean build for the G2v9i platform.

If you need to clean another platform, specify it as you would during compilation:

cd TinyG2 && make PLATFORM=OthermillPro clean
cd TinyG2 && make PLATFORM=G2v9i clean

Flashing the TinyG2

To get TinyG2 to reboot into SAM-BA mode, you can issue the json command {"boot":1}. You can also open & close the serial port at 1200 baud. The easiest way to do the latter is with the command stty -f /dev/tty.usbserial* 1200.

When in SAM-BA mode, we update firmware with the open source utility BOSSA (the SAM-BA version of avrdude). Our branch of it is here, though the open-source version can be used for standalone flashing.

To flash the program using BOSSA, use the following command template:

bossac -p tty.usbserialXX -e -w -v -b -R path/to/firmware.bin

Example:

bossac -p tty.usbmodem1411 -e -w -v -b -R g2/TinyG2/bin/G2v9i/G2v9i.bin

• -p specifies the serial port. It is likely to be /dev/tty.usbserialXX.
  • Important: -p prepends "/dev/", so if you supply the /dev/, it won't find the serial port.
• -e is erase
• -w is write,
• -v is verify (aka read back and check that it's valid).
• -b sets the machine to boot into firmware next time it reboots
• -R tells it to reboot.
• The last argument is the filename of the firmware, in .bin format.

Debugging

You can debug the TinyG through JTAG using a SAMA-ICE adapter and the JLink tools.

Installing JLink Tools

You will need to download and install the JLink software package from here. This will provide JLinkGDBServer, which we use for talking to the SAMA-ICE adapter.

Starting the JLinkGDBServer

You can start the JLinkGDBServer from the command line:

JLinkGDBServer -USB -device ATSAM3X8C -endian little -if JTAG -speed auto -noir

Connecting to the Device

Once the server is running, you can connect to the device using arm-none-eabi-gdb.

In the TinyG/ directory, run arm-none-eabi-gdb. gdb will mention that it connected to JLinkGDBServer.

We recommend running arm-none-eabi-gdb inside of the TinyG/ folder so that the .gdbinit file is detected.

Make Debug Command

You can build the code and open a debug terminal by adding debug to the build command:

make PLATFORM=OthermillPro debug

This will automatically connect to gdb. The JLinkGDBServer needs to be running.

Further Reading

• g2 wiki
• Bantam: Intro to V2 Firmware
• Bantam: Dev Instructions & Resources