7.10.6
Serial Interface Cable Wiring
The following are suggested cable wiring diagrams for connecting the Model 642 Serial Interface to various Customer
Personal Computers (PCs).
Model 642 DE-9P
5 - GND
2 - RD (in)
3 - TD (out)
4 - DTR (out)
6 - DSR (in)
1 - NC
7 - DTR (tied to 4)
8 - NC
Model 642 DE-9P
5 - GND
2 - RD (in)
3 - TD (out)
1 - NC
7 - DTR (tied to 4)
8 - NC
6 - DSR (in)
4 - DTR (out)
Model 642 DE-9P
5 - GND
2 - RD (in)
3 - TD (out)
1 – NC (out)
6 - DSR (in)
4 - DTR (out)
7 - DTR (tied to 4)
8 - NC
9 - NC
NOTE: Same as null modem cable design except PC CTS is provided from the Model 642 on DTR.
7.10.7
IEEE-488 Parallel Interface Connector
Connect to the IEEE-488 Interface connector on the Model 642 rear with cables specified in the IEEE-488-1978 standard
document. The cable has 24 conductors with an outer shield. The connectors are 24-way Amphenol 57 Series (or
equivalent) with piggyback receptacles to allow daisy-chaining in multiple device systems. The connectors are secured in
the receptacles by two captive locking screws with metric threads. The total length of cable allowed in a system is 2
meters for each device on the bus, or 20 meters maximum. The Model 642 can drive a bus of up to 10 devices. A
connector extender is required to use the IEEE-488 Interface and Relay Terminal Block at the same time. Figure 7-12
shows the IEEE-488 Interface connector pin and signal names as viewed from the Model 642 rear panel.
7-14
Lake Shore Model 642 Electromagnet Power Supply User's Manual
Model 642 to PC Serial Interface – PC with DE-9P
Standard Null-Modem Cable (DE-9S to DE-9S)
Model 642 to PC Serial Interface – PC with DB-25P
Standard Null-Modem Cable (DE-9S to DB-25S)
Model 642 to PC Interface using Null Modem Adapter
Null Modem Adapter
PC DE-9P
5 - GND
3 - TD (out)
2 - RD (in)
6 - DSR (in)
4 - DTR (out)
7 - RTS (out)
8 - CTS (in)
1 - DCD (in)
PC DB-25P
7 - GND
2 - TD (out)
3 - RD (in)
4 - RTS (out)
5 - CTS (in)
8 - DCD (in)
20 - DTR (out)
6 - DSR (in)
PC DE-9P
5 - GND
3 - TD (out)
2 - RD (in)
4 - DTR
1 - DCD (in)
6 - DSR (in)
8 - CTS (in)
7 - RTS (out)
9 - NC
Service