CANOGA PERKINS 2240 Fiber Optic Modem - Manual (Page 58)

2240 Fiber Optic Modem User Manual Chapter 4 Data Interfaces
Multi-Channel Interfaces
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cable. If this ground connection is present, and you prefer to use it, move the UNBAL_REF
jumpers to SC.
Factory setting: GND
4.6.8 RS-423/DB-25 Interface
NOTE: The maximum data rate for this interface is 9.6 kbps.
This interface is electrically compatible with EIA RS-423A. It will also operate with asynchronous
RS-232D systems.
This interface uses the physical connector type and pinouts specified in RS-232D (refer to
Table 4-10). The RS-423/232D interface uses a 25-pin, female D-type connector for the physical
connection.
There are six end-to-end control lead pairs. They are listed with the input signal listed first.
• TD to RD
• STD to SRD
• DTR to RI
• SRTS to SDCD
• DSRS to SCTS
• RTS to DCD
NOTE: If DTR to RI and STD to SRD are used on the RS232/RS366 port, these
control leads may not be available on 422/449 and V.35 interfaces.
Table 4-10. RS-423 Pinouts for Models MC1 and MC2
Pin
Number
RS-232 Pin
Name
(abbrev)
(full name) Direction
1 PG Protective Ground –
2 TD Transmit Data to modem
3 RD Receive Data from modem
4 RTS Request to Send to modem
5 CTS Clear to Send from modem
6 DSR DCE Ready from modem
7 SG Signal Ground - –
8 DCD Receive Line Sig. Det. from modem
12 SDCD Secondary Line Sig. Det. from modem
13 SCTS Secondary CTS from modem
14 STD Secondary TD to modem
16 SRD Secondary RD from modem