1
SC932A CS I/O to RS-232-DCE Interface
1. General Description
FIGURE 1-1. SC932A CS I/O to RS-232-DCE Interface
The SC932A (FIGURE
1-1
) is used to interface a Campbell Scientific
datalogger to any modem that is configured with an RS-232 DCE (Data
Communications Equipment) serial port. Features include:
•
True RS-232 signal levels.
•
Power for the SC932A is supplied from the 5 V supply on pin 1 of the
datalogger’s CS I/O port. The SC932A will use the 5 V supply to
power the RS-232 modem if needed.
•
Two-way (interactive) communication.
The SC932A is frequently used with a short haul modem to communicate
across a dedicated line made of two pairs of twisted wire with a shield. Section
3
,
Installation
(p. 3)
, describes the details of this application using a short haul
modem built by RAD.
The SC932A is also commonly used with the satellite transmitters, cellular
modems, and spread spectrum radios.
The SC932A does not support one-way output or printer communication. Data
transfer is blocked when pin 6 from the datalogger is high (SDE/printer
enable).
