RJ45 MALE CONNECTOR to the RocketPort card.
25 PIN D-SUB MALE to the modem
The Comtrol RocketPort is a multiport serial adapter that breaks out its ports through an external fan-out cable (Quadcable or Octacable) terminating in RJ45 connectors, which are then wired to standard D-subminiature connectors for modem or device connections. This cable connects one RJ45 port on the fan-out cable to a DB-25 male RS-232 DCE modem, carrying the standard TIA/EIA-232-F signals including TxD, RxD, RTS, CTS, DSR, DCD, and DTR. The RocketPort ports operate as DTE; a straight-through cable is used to a modem (DCE). Ring Indicator (RI) is not carried on the RJ45 connector.
| Description | RJ45 | D-Sub | Dir |
|---|---|---|---|
| Request To Send | 1 | 4 | OUT |
| Data Terminal Ready | 2 | 20 | OUT |
| Ground | 5 | 7 | OUT |
| Transmit Data | 3 | 2 | OUT |
| Receive Data | 6 | 3 | IN |
| Data Carrier Detect | 6 | 8 | IN |
| Data Set Ready | 7 | 6 | IN |
| Clear To Send | 8 | 5 | IN |
Notes
The RJ45 connector mates with the Comtrol Quadcable or Octacable fan-out cable. The DB-25 male connector attaches to the modem’s female DB-25 DCE port. Ring Indicator is not supported on the RJ45 interface; only eight signals are carried. Standard TIA/EIA-232-F voltage levels apply: Mark (logic 1) = −3 V to −15 V; Space (logic 0) = +3 V to +15 V.
Signals
- RTS — Request To Send; DTE asserts to indicate readiness to send data
- DTR — Data Terminal Ready; DTE asserts to indicate it is powered and ready
- GND — Signal Ground; common reference for all RS-232 signal levels
- TxD — Transmit Data; serial data sent from DTE (RocketPort card) to DCE (modem)
- RxD — Receive Data; serial data received by DTE from DCE
- DCD — Data Carrier Detect; asserted by modem when a carrier is detected on the line
- DSR — Data Set Ready; asserted by modem to indicate it is ready to communicate
- CTS — Clear To Send; asserted by modem to permit the DTE to transmit data