Hi,
I thought I would ask a general question before I dig deeper in to this topic. I have a lot of different boards lying around. Some Arduinos, FPGA boards and some ARM Cortex DVK's. None of these cards have DAC's that can operate at high quality audio bit ranges. So my question is simply: What is the best method of sending digital audio bit-streams from one of these cards to the Axoloti for processing or simply using the Axoloti as a DAC?
Hi, @MrCravon,
I think that an issue is the synchronisation between the boards.
If you're willing to hack and deal with unreleased bleeding edge development, the migration_to_chibios16 branch contains code to transmit/receive digital audio over SPI in packets of 16 sample intervals on the X3 pinheader, using the jt/link/audio object. You will need to compile everything yourself, use "dfu flashing" to flash firmware, and be ready to dig out a logic analyzer or oscilloscope for diagnostics. Easiest if your device takes the SPI slave role, and Axoloti master. 8bit Arduinos won't be able to handle the bitrate (nor add any useful audio processing capacity to Axoloti). The "GUI-refactoring" branch currently still needs further (ongoing) development to get into a usable state, so do not try that yet.
The main reason for my question is that I wanted to try making some DSP blocks in VHDL on an FPGA board I have. Not to add functionality to the axoloti but rather for learning to do DSP on an FPGA. I thought it might be easier to send bit streams to and from the axoloti rather than implementing some source of audio and DAC myself. I have some experience with FPGAs but never with audio and think it would be fun.
Thanks for the responses and for pointing me in the right direction. I'll post here if I decide to make time and go ahead with trying this.