Raspberry Pi Pico emulating a General Instruments SP0256 in Wilf Rigter's ZX Voice, for the Timex/Sinclair 2068.
- https://archive.org/details/zx-appeal/ZX-Appeal%20Oct%2086/page/n7/mode/1up
- https://archive.org/details/zx-appeal/ZX-Appeal%20Jul-Aug%2086/page/n1/mode/2up
- https://archive.org/details/zx-appeal/ZX-Appeal%20Mar%2087/page/n7/mode/2up
- https://archive.org/details/zx-appeal/ZX-Appeal%20Apr%2087/page/8/mode/1up
- https://archive.org/details/analog-computing-magazine-29/page/n59/mode/2up
This project builds on the work of these two projects:
- https://github.com/blackjetrock/pico-sp0256
- https://github.com/ExtremeElectronics/SP0256-AL2-Pico-Emulation-Detail
and contains code that drives the PWM to generate the audio from the phoneme data which is at this project:
https://www.cpcwiki.eu/index.php/SP0256_Allophones
