Campbell Scientific SC32A User Manual

SC32A Optically Isolated

RS232 Interface

Revision: 1/93

Copyright © 1987-1993

Campbell Scientific, Inc.

Warranty and Assistance

The SC32A OPTICALLY ISOLATED RS232 INTERFACE is warranted
by CAMPBELL SCIENTIFIC, INC. to be free from defects in materials and
workmanship under normal use and service for twelve (12) months from date
of shipment unless specified otherwise. Batteries have no warranty.
CAMPBELL SCIENTIFIC, INC.'s obligation under this warranty is limited to
repairing or replacing (at CAMPBELL SCIENTIFIC, INC.'s option) defective
products. The customer shall assume all costs of removing, reinstalling, and
shipping defective products to CAMPBELL SCIENTIFIC, INC. CAMPBELL
SCIENTIFIC, INC. will return such products by surface carrier prepaid. This
warranty shall not apply to any CAMPBELL SCIENTIFIC, INC. products
which have been subjected to modification, misuse, neglect, accidents of
nature, or shipping damage. This warranty is in lieu of all other warranties,
expressed or implied, including warranties of merchantability or fitness for a
particular purpose. CAMPBELL SCIENTIFIC, INC. is not liable for special,
indirect, incidental, or consequential damages.

Products may not be returned without prior authorization. The following
contact information is for US and International customers residing in countries
served by Campbell Scientific, Inc. directly. Affiliate companies handle
repairs for customers within their territories. Please visit
www.campbellsci.com to determine which Campbell Scientific company
serves your country. To obtain a Returned Materials Authorization (RMA),
contact CAMPBELL SCIENTIFIC, INC., phone [phone]. After an
applications engineer determines the nature of the problem, an RMA number
will be issued. Please write this number clearly on the outside of the shipping
container. CAMPBELL SCIENTIFIC's shipping address is:

CAMPBELL SCIENTIFIC, INC.

RMA#_____
815 West 1800 North
Logan, Utah 84321-1784

CAMPBELL SCIENTIFIC, INC. does not accept collect calls.

SC32A OPTICALLY ISOLATED RS232 INTERFACE

1. FUNCTION

The SC32A interfaces an RS232 peripheral,
commonly a computer or printer, to the Serial
I/O of a CSI datalogger. The SC32A replaces
the SC32. Functions include:

1. Converting datalogger logic levels to RS232
logic levels.

2. Optically isolating the datalogger and the
RS232 peripheral. Optical isolation
separates the SC32A into a datalogger
section and an RS232 section. Signals
entering from either side are electrically
independent, protecting against ground
loops, normal static discharge, and noise.

3. Passing data when pins 5 or 6 of the
datalogger I/O are high and the on-board
jumper is removed (see SC32A Component
Location Diagram, Figure 5.1).

4. Passing data when pin 5 is high and pin 6 is
low when the jumper is in place.

SC32As with serial numbers less than 1500
were shipped with the jumper in a blocking
position (two posts connected). Serial numbers
1500 and greater are shipped with the jumper
on one post only, in the passing position.

When used with a CR10 Measurement and
Control Module, the correct SC32A jumper
position depends on the application. For all

other CSI dataloggers, the jumper has little
effect and could be removed (Section 5).

2. SPECIFICATIONS

Operating temperature: -25 to +50 °C (typical)
Power: Powered by host devices, see

"Operation" section
Ports: 25 pin (sockets) configured as DCE. 9

pin (pins) connect to CSI datalogger through
SC12 Two Peripheral Cable (included)

Size: 2.25 x 1.0 x 3.5 inches, 0.25 lbs.

3. CONNECTOR DESCRIPTIONS

3.1 25 PIN

The SC32A 25 pin female port is configured as
Data Communications Equipment (DCE) for
direct cable connection to Data Terminal
Equipment (DTE). Most terminals, computers,
and printers are configured as DTE. For
connection to DCE devices such as modems
and some computers, a null modem is required.
A null modem configuration is given under
"Special Cases", Section 5.3.

3.2 9 PIN

The SC32A 9 pin male port connects to the
datalogger through the SC12 Two Peripheral
Cable supplied with the SC32A. Pin
descriptions and direction (Input/Output) are
given in Table 3.1.

TABLE 3.1 SC32A CONNECTOR DESCRIPTIONS

25 PIN FEMALE CONNECTOR 9 PIN MALE CONNECTOR

PIN # I/O
1 GROUND 1 IN +5V

2 IN TX 2 GROUND
3 OUT RX 3 OUT RING
4 IN RTS (POWER) 4 OUT RX
5 OUT CTS 5 IN ME
6 OUT DSR 6 IN PE (CR10 SDE)
7 GROUND 9 IN TX
8 OUT DCD
20 IN DTR (POWER)

DESCRIPTION PIN # I/O DESCRIPTION

1