Omega A2400 User Manual

Page 43

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SetUp Command 5-4

Byte 2
Byte 2 is used to configure some of the characteristics of the communica-
tions channel; linefeeds, parity, and baud rate.

Linefeeds
The most significant bit of byte 2 (bit 7) controls linefeed generation by the
module. This option can be useful when using the module with a dumb
terminal. All responses from the modules are terminated with a carriage
return (ASCII $0D). Most terminals will generate a automatic linefeed when
a carriage return is detected. However, for terminals that do not have this
capability, the modules can generate the linefeed if desired. By setting bit 7
to ‘1’ the module will send a linefeed (ASCII $0A) before and after each
response. If bit 7 is cleared (0), no linefeeds are transmitted.

When using the ‘#’ command prompt, the linefeed characters are not
included in the checksum calculation.

Parity
Bits 5 and 6 select the parity to be used by the module. Bit 5 turns the parity
on and off. If bit 5 is ‘0’, the parity of the command string is ignored and the
parity bit of characters transmitted by the module is set to ‘0’.

If bit 5 is ‘1’, the parity of command strings is checked and the parity of
characters output by the module is calculated as specified by bit 6.

If bit 6 is ‘0’, parity is even; if bit 6 is ‘1’, parity is odd.

If a parity error is detected by the module, it will respond with a PARITY
ERROR message. This is usually caused by noise on the communications
line.

If parity setup values are changed with the SU command, the response to
the SU command will be transmitted with the old parity setup. The new parity
setup becomes effective immediately after the response message from the
SU command.

Baud Rate
Bits 0-3 specify the communications baud rate. The baud rate can be
selected from ten values between 300 and 115200 baud. Refer to Table 5.2
for the desired code.

The baud rate selection is the only setup data that is not implemented
directly after an SU command. In order for the baud rate to be actually

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