elms / py_ice40

python code to configure iCE40 FPGAs

Goal

Generalized utility to configure iCE40 from SBC.

Why no iceprog?

iceprog is great if you are using an FTDI chip. The idea is to have one tool for beginners and experts that can support most if not all iCE40 dev boards.

How to use

sudo ./py_ice40/example_config.py <binfile>

Troubleshooting

1. If you get a SPIError check that the the SPI device is enabled and present ls /dev/spidev*

   To enable on Raspberry Pi:

   sudo raspi-config nonint do_spi 0

2. GPIOError

   Check that you have GPIO enabled and have permission:

   ls -l /sys/class/gpio

Sketch of plan

top level options

• speed
• flash or sram
• flash
  • offset
  • command set?

SPI - spi operations and encapsulation

SRAM - logic with reset and SS to put into slave mode

• cdone

FLASH - commands and logic for interacting with SPI Flash

• hold ice40s in reset
• set of flash commands

Intrepid

• add option for fpga 1 or 2
• different SS, reset, and cdone
• auxilary switch
• support reset of multiple for flash

Hardware support spidev and gpio

• bitbang
• FTDI chips
• USB id

TODO

• config FPGA
• flash access
• options compatible with iceprog
• Device interfaces
  • SPIdev/GPIO support
  • FTDI support
  • FX2 support