NEC PC-98 is the Japanese PC standard with a proprietary C-Bus expansion connector, used in NEC PC-9801 and PC-9821 computers from 1982 to 2003 for graphics cards, sound cards, and modems.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1 | MASTER | Bus master request | I/O |
| 2 | GND | Ground | GND |
| 3 | +5V | 5V power | PWR |
| 4 | IRQ3 | Interrupt request 3 | I/O |
| 5 | D0 | Data bit 0 | I/O |
| 16 | D15 | Data bit 15 | I/O |
| 17 | A0 | Address bit 0 | I/O |