Measurement Computing TempScan/1100 - Manual (Page 23)

TempScan / MultiScan User’s Manual 899493 System Overview 1-9
RS-232/RS-422 Serial Configuration
Alternatively, the TempScan/1100 or MultiScan/1200 unit can be controlled through its serial port
connector. Complete serial port configuration is accomplished by using both internal jumpers and DIP
switch settings. The internal jumpers, located on the main board behind each serial connector, are used to
configure the port with either RS-232 or RS-422 electrical characteristics. The DIP switch, located on the
rear panel, is used to determine handshaking, parity, and baud rate. Furthermore, the selection of an
RS-232 or RS-422 electrical configuration determines the serial port pattern of pin connector signals, as
discussed later.
Internal Jumpers
The jumpers within the unit configure the serial port electrically as either RS-232 or RS-422. To change
the serial port configuration, it is necessary to perform the following steps:
WARNING
Never disassemble the case while it is connected to the AC power line!
Internal voltage potentials exist which could cause bodily injury or death!
WARNING
Never disconnect the AC power line from the TempScan/1100 or MultiScan/1200
while its scanning cards are connected to an external device! Common mode
voltage potentials exceeding 60 VDC or 30 Vrms at the terminals, may exist which
could cause bodily injury or death!
Note: If disassembly or disconnections are necessary, first turn off the power, then disconnect the
scanning cards, next disconnect the AC power line, and then any other cables, prior to unit
disassembly.
To Change the Serial Configuration
1. Turn off the power, disconnect the scanning cards, the power line cord, then all other cables from the
unit. For more information, see section Disconnecting & Reconnecting the System During Setup on
page 1-6.
2. Place the unit on a flat surface. Remove the six screws on top of the case. Remove the top cover.
3. The serial port is capable of operating in RS-232 or RS-422 mode. This selection is done via a set of
hardware jumpers located on the main board behind the serial connector. A 12-position jumper plug
must be inserted in one of the two available positions for proper operation (across JP11 and JP12 for
RS-232, across JP12 and JP13 for RS-422). These jumpers are factory set for RS-232 as shown in the
figure. To reconfigure the serial port for RS-422 operation, remove the jumper plug and reinsert it
into the lower 2 rows of jumpers.