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This project is part of the Elf Cube. A 1970's retro computer system based on the RCS CDP1802 8 bit microprocessor.
The backplane can accept up to 6 adapter cards, one of which must be a processor card. It supplies power to any installed adapter cards, and provides the system clock, power-on-reset, and bus pull up resistors.
| Jumper | Description |
|---|---|
| JP1/2/3 | Install a jumper on ONE of these to select the system clock speed (1/2/4 MHz) |
| JP4 | Selects whether power is direct from USB, or regulated from the 5.5mm Jack socket. |
| Connector | Description |
|---|---|
| J1 | Bus extension - IN. Can connect to another Backplane or adapter card. When cascading Backplanes, additional ones should only be populated with the 2x20 connectors. |
| J2 | First adapter slot. D+/D- from the USB connector are routed to this slot (pins 15,34) |
| J3/4/5 | Adapter slots |
| J7 | Bus extension - OUT. |
| J10 | Reset connector, for connection to an external reset button, in addition to the onboard one. |