serial interface cable
9 pin D-SUB female connector to the computer
The Ricochet SX is a later-generation model in Metricom’s Ricochet family of wireless packet modems, which operated in the licence-free 902–928 MHz ISM band at 100 kbps RF data rate. Like other modems in the family, the SX presents an AT-compatible (Hayes command set) RS-232 serial interface to the host PC via a DE-9 connector, conforming to ANSI/TIA/EIA-232-F. The DE-9 DTE pin assignments follow the standard order: pin 1 DCD, pin 2 RD, pin 3 TD, pin 4 DTR, pin 5 GND, pin 6 DSR, pin 7 RTS, pin 8 CTS, pin 9 RI. The Ricochet SX was released after the 1997 edition of Metricom’s official reference guide, and no manufacturer specification for the SX cable has been published.
Notes
The Ricochet SX is distinct from the Phase I, Phase II, and Ricochet SE variants documented in Metricom’s 1997 reference guide; those earlier models use RJ-45 or proprietary 14-pin connectors. The SX cable uses a DE-9 female connector on the computer side. Pin assignments for the modem end are not publicly documented by Metricom.
References
- Low-Voltage, Single-Supply 232-Standard Interface Solutions (SLLA083A) — Texas Instruments; RS-232 (TIA/EIA-232-F) electrical and signal specifications
- Ricochet Modem Reference Guide — Metricom, Inc., 1997; official cable pinouts for SE, Phase I, and Phase II variants