286, SPI, and a 6522 VIA
Updated: Dec 1, 2022
I recently added basic SPI support to my 80286 system with the help of a W65C22S Versatile Interface Adapter (VIA).
Additional Reading About SPI
I am currently using a programmable system-on-chip (PSoC) from Cypress to handle address decoding. Below is the current configuration of the PSoC.
The following schematic is as of 23 November 2022.
This assembly I used during this video is available on my GitHub: Assembly Used in Video.
MAX7219/MAX7221 - Serially Interfaced, 8-Digit LED Display Drivers (maximintegrated.com)
SPI + Arduino Nano = Serial Debugger
x86/g1_20221127.asm at main · rehsd/x86 (github.com)
x86/SPI_80286_Nano.ino at main · rehsd/x86 (github.com)
SD Card Support
I have now added support to read from an SD card.
I have an older post that contains some of my previous (troubleshooting) work with SPI and SD cards. See Calling All SPI SD Card Wizards: Troubleshooting SD Card Access with SPI (rehsdonline.com).
The assembly code used in the above video is available here: x86/g1_20221130.asm at main · rehsd/x86 · GitHub.