Hardware

In it’s current incarnation, the Steckschwein consists of 3 main units:

1. CPU/Memory
2. IO (VIA 65c22), now also including UART
   1. SPI-Devices
   2. UART 16550
   3. Joysticks and user port
3. Video / audio board with V9958 VDP and YM3812 (OPL2) sound chip

The 62c22 VIA is mainly utilized as SPI master to implement SPI as the main peripheral bus, connecting SD-card, RTC and the ATmega8 (used as PS/2 controller) to the system. The block diagram shows how things are working together.

Schematics, pcb layouts and firmware can be found at our Github repository.

Block diagram as PDF