CompactFlash is a 50-pin parallel ATA memory card still popular in professional DSLRs, supporting UDMA 7 at up to 167 MB/s.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1 | GND | Ground | GND |
| 2 | D3 | Data bit 3 | I/O |
| 3 | D4 | Data bit 4 | I/O |
| 6 | D7 | Data bit 7 | I/O |
| 7 | CS0# | Chip select 0 | I/O |
| 13 | VCC | 3.3V or 5V supply | PWR |
| 21 | D0 | Data bit 0 | I/O |
| 26 | CD1# | Card detect 1 | I/O |
| 31 | D15 | Data bit 15 | I/O |
| 41 | RESET# | Reset active low | I/O |
| 48 | RDY/BSY# | Ready or Busy | I/O |
| 49 | VCC | Power supply | PWR |
| 50 | GND | Ground | GND |