9 pin D-SUB Female to the PA-RISC Computer
25 pin D-SUB Male to the Serial White Console
The white console cable for HP PA-RISC (HP 9000) workstations connects the machine’s asynchronous serial console port to a terminal or PC. It carries RS-232 (EIA/TIA-232) signals, the electrical standard governing unbalanced serial communication over D-SUB connectors. One end terminates in a 9-pin D-SUB female plug at the computer and the other in a 25-pin D-SUB male plug at the serial console, with the signal wiring adapted between the two connector sizes.
| DB9 | DB25 |
|---|---|
| 1 | 4 |
| 2 | 2 |
| 3 | 3 |
| 4 | 5 + 6 |
| 5 | 7 |
| 6 | 20 |
| 7 | 8 |
| 8 | 20 |
| 9 | NC |
Signals
- DB9 pin 1 / DB25 pin 4 — RTS (Request to Send), hardware handshake output
- DB9 pin 2 / DB25 pin 2 — TXD (Transmitted Data), serial data output from DTE
- DB9 pin 3 / DB25 pin 3 — RXD (Received Data), serial data input to DTE
- DB9 pin 4 / DB25 pins 5+6 — DSR/CTS (Data Set Ready and Clear to Send), handshake inputs tied together
- DB9 pin 5 / DB25 pin 7 — GND (Signal Ground), common reference
- DB9 pin 6 / DB25 pin 20 — DTR (Data Terminal Ready), handshake output
- DB9 pin 7 / DB25 pin 8 — CTS (Clear to Send), handshake input
- DB9 pin 8 / DB25 pin 20 — DSR (Data Set Ready), tied with DTR at DB25 pin 20
- DB9 pin 9 — NC (not connected)
Notes
- The DB9 end follows the standard RS-232 DE-9 signal layout: TXD=pin 2, RXD=pin 3, RTS=pin 7, CTS=pin 8, DTR=pin 4, DSR=pin 6, DCD=pin 1, GND=pin 5 — however the mapping here shows the DB9 connector as presented at the PA-RISC computer port, which uses a different signal assignment consistent with a DTE console interface.
- DB25 pins 5 and 6 (CTS and DSR on the DB25 side) are tied together and connected to DB9 pin 4; this is a common loopback arrangement to satisfy handshake requirements.
- DB25 pin 20 (DTR) appears twice in the table: at DB9 pin 6 and again at DB9 pin 8, reflecting a further handshake tie between DTR and DSR on the 25-pin side.
- Default console baud rate for HP PA-RISC systems is typically 9600 bps, 8 data bits, no parity, 1 stop bit (8N1), no hardware flow control.
References
- HP 9000 A-Class (A180) User’s Manual — 9-pin RS-232 console port — Hewlett-Packard.
- TIA/EIA-232-F — Interface Between Data Terminal Equipment and Data Circuit-Terminating Equipment Employing Serial Binary Data Interchange (Telecommunications Industry Association).