3090

3090 is the first ND-110 CPU board (referred to as the "old" CPU card). It contains the CPU, bus arbitration logic, memory control, cache memory and other subsystems, including the Real time clock and the I/O for the serial console.

Switches and indicators
The following switches and indicators are on the card Location 29J - potentiometer Location 28J - ALD edge switch Location 26J - baud rate edge switch Location 21J - self test lamp (green) Location 19J - running lamp (red) Location 15J - cache on lamp (red) Location 13J - cache on/off switch

Connectors
The A and B connectors are used for I/O, the C connector is used for the ND-100 Bus.