rubin@mtuxn.UUCP (M.RUBIN) (09/05/85)
These are the ACTUAL pinouts of the 3B2's strange 8-pin modular RS232 connector, and all the known flavors of TRW modular-to-DB25 adapter (part number 232-21-25-xxx) for the 3B2, determined by inspection. It seems they did quite a bit of hacking to disguise the lack of a DSR pin. Note that the modular-modular CABLES supplied with the 3B2 are crossed over (1->8, 2->7, etc.) and the tables below assume the use of such a cable. Also note the adapter pinout list in the Appendix of the 3B2 Owner/Operator's manual is WRONG!! Yes, the male and female "Terminal/Printer" connectors are DIFFERENT. DB25 PINOUTS (see below for abbreviations) #010 #006 #008 #005 3B2 3B2 Male Female Male Male MODULAR receives sends Term./ Term./ Remote/ ACU/ PINOUTS Printer Printer Console Modem -------- -------- -------- ----- ----- ----- ----- 1 "Prot.Grd." 1 FG 1 FG 1 FG 1 FG 2 "Reserved"(CTS) <-- 4 RTS 4 RTS 5 CTS 5 CTS 3 "TXDO" <-- 3 RxD 3 RxD 2 TxD 2 TxD 4 "DTRO" <-- 8 DCD 8 DCD 6 DSR, 20 DTR 20 DTR | 5 "RXDO" --> 2 TxD 2 TxD 3 RxD | 3 RxD | 6 "DCDO" --> 6 DSR, 6 DSR 6 DSR,| 8 DCD 20 DTR 20 DTR 7 "Signal Grd." 7 SG 7 SG 7 SG 7 SG 8 "Reserved"(RTS) --> 5 CTS 5 CTS 4 RTS 4 RTS --------------------------------------------------------------------- DB25 RS-232-C "Standard" :-) PIN ABBR. NAME DIRECTION ---- ---- ---- -------------- 1 FG Frame Ground -- 2 TxD Transmit Data to DCE 3 RxD Receive Data to DTE 4 RTS Request to Send to DCE 5 CTS Clear to Send to DTE 6 DSR Data Set Ready to DTE 7 SG Signal Ground -- 8 DCD Carrier Detect to DTE 20 DTR Data Terminal Ready to DCE