Expandability and simplicity. I've designed a low pin-count bus named SkinnyBus8. It has I2C, SPI, slot select and power. 8 pins in total per slot.
Each slot has a separate slot select. When the slot is selected, it is possible to request info via the I2C-bus to a 256-byte eeprom that contains info about the expansion card. PlugAndPlay :D
The SPI-bus is used for the main function on each slot.
A MicroPython-board is the "mainboard", and I've built a SkinnyBus8 4-slot expander-card. Coding in Python to test the card-functions has been a true pleasure. Genuinely fast prototyping.Boards built so far:
- 4-slot expansion board
- 128KiB SRAM
- 128KiB EEPROM
Working, and awaiting a proper board is an MCP23S17 SPI-GPIO chip connected to a 40x3 alphanumeric LCD.
The name SkajNätt is the Swedish pronunciation of Skynet, and Nätt means small. One computer to rule them all...