After taking part in the very enjoyable RetroChallenge in 2024 and 2025, I’ve decided to take part again in 2026.
This year, my plan is to use the SPI prototcol so my RC2014 computer can talk to various other SPI supporting devices.
SPI stands for Serial Peripherial Interface. It uses synchronous serial communication allowing a “master” to talk to “slave”. This gives us two lines MOSI – Master Out Slave In, and MISO – Master In Slave Out. There is a also a Clock line where 1 bit of data is sent and received each pulse of the clock, and a Select line that is used to activate a device. This allows multiple devices to share the same Clock, MOSI, and MISO lines, while using individual Select lines.
The Z80 microprocessor the RC2014 uses does not natively support SPI, so I will need to put together some basic hardware as well as writing software to support it.