CANOGA PERKINS 2240 Fiber Optic Modem - Manual (Page 57)

2240 Fiber Optic Modem
57
Table 4-F.
Pinout Differences
(-435 vs. -436)
NOTE: The previous V.35 interface, Model -435, did not conform to
the ISO 2593 pinout and was the predecessor to the -436 interface.
The signals listed in Table 4-F have different pinouts on the -435
versus the -436. The -435 also did not support the Extra Clock for
the receive data signal. This pinout difference table is only included
as a reference.
None of the control leads interact with the data transmission. They are provided in
order to comply with a variety of DTE interface requirements. Most of the control
leads are actually end-to-end signal channels which can be used for any purpose as
long as it conforms to the V.35 interface standards.
The RTS, CTS and DCD pins function together to provide the most common
handshake functions. An input to RTS (see description of RTS-Bias jumper) is
transmitted to the DCD output at the other end of the link (see description of DCD
jumper). CTS follows RTS locally but it is delayed by approximately 1 msec when
RTS turns on (see description of CTS-Gate jumper). There are two other end-to-
end control lead pairs. They are listed below with the input signal listed first:
DTR to RI
STD to SRD
Data Set Ready (DSR) typically indicates that the modem is ready to handle
transmit data. During loopbacks, the behavior of this signal is dependent on the
position of the DSR jumper (see description of DSR jumper). Test Mode (TM) is
turned ON (asserted) ONLY when a loopback is active on either one or both
modems.
Function Pin CCITT Direction
(A/B) Circuit Number
Test Indicator C C 142 from modem
Secondary Receive Data L 119 from modem
Local Loopback E E 141 to modem
Remote Loopback D D 140 to modem