3.2 CONNECTING THE SUB-CHANNELS
The two asynchronous, serial sub-channels of the Model 3022 are
RJ-45 female ports that conform to the EIA/TIA-561 interface (see
Figure 1, below). These ports connect to the two serial devices that will
be multiplexed through the main RS-232 port of the Model 3022. Any
combination of RS-232 devices may be connected to the Model 3022's
sub-channels: PCs, terminals, printers, laptops, Macs, plotters, etc.
Every serial device connected to channels 1 and 2 must have a
special interface cable. On one end, this interface cable must have an
RJ-45 male plug; on the other end, it must have a connector that fits
into your RS-232 serial device. The diagrams below and on the
following page show pin connections between the Model 3022's sub-
channels and common RS-232 serial interfaces. You may use these
diagrams to construct your own cables, or you may purchase pre-made
cables from Patton Electronics. See Appendix B for Patton cable part
numbers.
PC/XT™ or Serial Printer to Model 3022 Pin-Outs:
Serial DB-25
Model 3022 RJ-45
Pin No.
Pin No.
6 (DSR) ------------------------------------- 1
8 (CD) --------------------------------------- 2
20 (DTR)------------------------------------ 3
7 (SG) --------------------------------------- 4
3 (RX Data) -------------------------------- 5
2 (TX Data)--------------------------------- 6
5 (CTS)-------------------------------------- 7
4 (RTS)-------------------------------------- 8
(continued)
PC/AT™ to Model 3022 Pin-Outs:
Serial DB-9
Model 3022 RJ-45
Pin No.
Pin No.
6 (DSR) ------------------------------------- 1
1 (CD) --------------------------------------- 2
4 (DTR) ------------------------------------- 3
5 (SG) --------------------------------------- 4
2 (RCV Data) ------------------------------ 5
3 (TX Data)--------------------------------- 6
8 (CTS)-------------------------------------- 7
7 (RTS)-------------------------------------- 8
3.3 CONNECTING TWO MODEL 3022s BACK-TO-BACK
You may connect two Model 3022s back-to-back, bypassing the
modems. To do this, you must have two Patton Model 3P–MF power
supply adapters (see Section 3.5), and one DB-25 female-female RS-
232 cable. The cable should be no longer than 100 feet (shorter in
some cases), and wired as a "null modem" or "crossover". The
following table shows how to pin a null modem cable that will connect
two Model 3022s back-to-back:
DB-25
Female
DB-25
Female
Pin No. Circuit
Circuit
Pin No.
1
AA -----------------------------------AA
1
2
BA -----------------------------------BB
3
3
BB -----------------------------------BA
2
4
CA -----------------------------------CB
5
5
CB -----------------------------------CA
4
6
CC ----------------------------------CD
20
7
AB -----------------------------------AB
7
9
Pwr ----------------------------------Pwr
9
20
CD ----------------------------------CC
6
Connect the Model 3P-MF adapters to the Model 3022 DB-25
ports. Then connect the null modem cable between the adapters. Do
not plug the adapters into their respective AC outlets until the serial
device connections have been made to the Model 3022s.
5
6
Figure 1. EIA/TIA-561 Interface pinouts for Model 3022 RJ-45 jacks (ports 1 & 2).
1 (DSR) from 3022
2 (CD) from 3022
3 (DTR) to 3022
4 (SG)
5 (RX Data) from 3022
6 (TX Data) to 3022
7 (CTS) from 3022
8 (RTS) to 3022
1
2
3
4
5
6
7
8
