Desk Viking
This is an STM32F103 debug tool inspired by the Bus Pirate. The aim is to have something that's easier to extend (I hate the PIC ecosystem) and a bit beefier - e.g. by having a proper USB connection instead of a USB<->UART bridge.
At present the code presents the device via 2 USB ACM devices. The first is the CLI interface, the second provides debugging information during development. The longer term plan is to present 2 interfaces (or 3 when debug is enabled) with the additional interface being a UART bridge to one of the device UARTs.
User interface
The user interface is designed to be compatible (though not identical to) the Bus Pirate interface; primarily because I'm already familiar with that and it provides a good set of initial functionality.
Supported protocols
The protocols currently supported are:
- 1-Wire
- CCLib/Proxy (debugging/programming of Texas Instruments CCxxxx chips)
- I2C
Building
desk-viking uses the lightweight Chopstx RT thread library. You'll need to get it as follows:
git clone https://salsa.debian.org/gnuk-team/chopstx/chopstx.git ../chopstx
Then configure the board you're using. My development is currently done using a Maple Mini, so I do:
ln -s ../chopstx/board/board-maple-mini.h board.h
If you're building on Debian you can get an appropriate cross compile via:
sudo apt install gcc-arm-none-eabi
After that you can build with a simple:
make
You'll get a build/desk-viking.bin file which can be flashed over a serial connection to the device's UART1 using stm32flash:
stm32flash -w build/desk-viking.bin -v /dev/ttyUSB0
Emulation mode
It's possible to compile desk-viking in "emulation" mode, where it is a standard Linux binary that can be connected to via USBIP. While this doesn't provide any emulation of a connected device it does allow testing of basic functionality. A VCD file is written with details of the various GPIO states, and this can be used with tools such as sigrok to verify operation is as expected.
To build in emulation mode, first link the Chopstx emulation header as the board file:
ln -s ../chopstx/board/board-gnu-linux.h board.h
Then compile:
make EMULATION=1
And run the resulting binary:
build/desk-viking
Then, as root, load the USBIP driver module (I found this didn't get auto-loaded):
modprobe vhci-hcd
And attach to the desk-viking exported device:
usbip attach -r 127.0.0.1 -b 1-1
When you're done you can detach the device cleanly with:
usbip detach -p 0
Once you've detached the desk-viking binary will exit and the VCD file will be written.
Pinouts
The pinout configuration can be configured in include/gpio.h. The default maps as follows:
| Name | STM32 GPIO | Maple Mini pin |
|---|---|---|
| AUX | PB8 | 18 |
| CLK | PB13 | 30 |
| CS | PB12 | 31 |
| MISO | PB14 | 29 |
| MOSI | PB15 | 28 |
These pins have been chosen as they map to SPI2, which should allow for the STM32 hardware SPI engine to be used for accelerating SPI access, rather than having to bitbang it.
TODO
This is a fledgling project and there is much to do.
Access methods
The intent is to implement various binary access methods that are not incompatible with each other, allowing the use of tools which already support those protocols to use the Desk Viking without modification. Primarily these are the Bus Pirate binary modes (BBIO, RAW, I2C + 1-Wire are already supported), but the CCLib CCProxy protocol is also implemented in a co-existing manner and it looks possible to implement the SUMP logical analyser protocol too.
| Tool | Protocol | Status |
|---|---|---|
| AVRDUDE | Bus Pirate binary SPI mode | Planned |
| CCLib | CCProxy | Supported |
| flashrom | Bus Pirate binary SPI mode | Planned |
| OpenOCD (SWD) | Bus Pirate Binary RAW mode | Supported |
| OpenOCD (JTAG) | Bus Pirate OpenOCD mode | Planned |
| sigrok | SUMP | Planned |
Protocols
- CC.Debugger
- JTAG/SWD
- SPI
Author
License
This project is licensed under the GPL 3+ license, see COPYING for details.