Baud Rate Selection - Black Box 202T User Manual

The default setting for SW2 is positions 1–5 OFF and position 6 ON.
If you need to field configure a Modem 202T, you will need the following
information.
1. Baud rate of the serial device you are connecting with (unless using simplex).
2. Character format (1 start bit + # data bits + parity + 1 stop bit). This must add
to 10 or 11 bits.
Set SW2-3 ON = 11 bits, or OFF = 10 bits.
3. Use of RTS line from your equipment to control the flow of data into and
between modems. If RTS use is unknown, set the unit for DSCC DataSense
mode.
Set SW2-4
4. Either 1 wire pair (2-wire mode) or 2 wire pairs (4-wire mode). Set SW3.
5. Half or full duplex data transmission method, bi-directional or one-way data
flow (simplex). Set SW2-5 and SW2-6 using the information in Table 4-2.
After changing any switches, remove DC power and reapply to
memorize the changes. Switches are only read during power on.

5.2 Baud Rate Selection

The Modem 202T will operate at 300, 600, and 1200 baud in a 10- or 11-bit word
format. The modem is parity transparent; however, it must know if there are 8 or 9
bits of data/parity. In Simplex mode, the Modem is baud-rate and protocol
transparent and the baud switches are ignored. The Baud rate is set using switches
SW2-1 and SW2-2.
Baud Rate
*1200
600
300
Not Used
*Default
OFF = DSCC DataSense
Table 5-1. Selecting the baud rate.
SW2-1
OFF
ON
ON
OFF
NOTE
ON = RTS
NOTE
SW2-2
OFF
OFF
ON
ON
CHAPTER 5: Operation
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