default firmware for doppler

2 bytes SPI fullduplex sequence

input to led matrix
output from gpios and buttons see pcf file file for pin mapping

Based on https://github.com/noscene/Doppler_FPGA_Firmware/tree/master/doppler_simple_io

Can be build using icestorm docker image - see https://github.com/noscene/Doppler_FPGA_Firmware#build

Can also be build directly, if icestorm and arache-pnr are installed

additional stuff

Avoid absolut names by coping header-file to arduino_dir
Removed weird upload of default firmware (ice40.upload())
Added make.sh to build in Docker with correct permissions
Removed need for renaming var in .h file

scripts

make.sh - compile fpga AND arduino project, upload to doppler.

Eg: $ PROJ=doppler_custom ./make.sh FPGA project in doppler_custom.v and arduino project in doppler_custom_arduino/doppler_custom_arduino.ino

Or: $ PROJ=miditest ./make.sh

projs

synth.v

A sine-wav, frequence modulated by a saw wave

miditest.v

Turns the Doppler into a midi-enabled synth (really just enables Midi on and Midi off for now).

Requires the MIDIUSB.h library installed, which makes the Doppler expose a MIDI device over USB.

Install like this:

arduino-cli lib install MIDIUSB

After the Arduino project has been uploaded to the Doppler, check that the midi device is active:

$ aplaymidi --list
 Port    Client name                      Port name
 14:0    Midi Through                     Midi Through Port-0
 20:0    doppler                          doppler MIDI 1

The playmidi.sh script continuously plays the miditest.mid file on the Doppler.

For now it just turns amp on/off on midi on/off.

AArch64

The Doppler requires a few "cores" (confusingly referred to as "Boards" in the Arduino IDE):

Adafruit SAMD Boards
dadamachines - M4 Boards

This is nicely described here: https://github.com/dadamachines/arduino-board-index/blob/master/README.md

However, the old "Adafruit SAMD Boards" v1.3 isn't compatible with Aarch64, and the Doppler core is hard-wired to use v1.3 (or similar old version).

To fix this, install a newer version of "Adafruit SAMD Boards" (eg 1.7.13), then install the old version of the "dadamachines - M4 Boards" and patch it up, like so:

$ cd ~/.arduino15/packages/dadamachines - M4/hardware/samd/1.3.1
$ patch < /path/to/doppler_custom/doppler_aarch64_patch.diff

grav / doppler_custom