Milltronics AiRanger SPL PL-573, Instruction Manual

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Page 98 AiRanger SPL PL-573
Technical Refer
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Communication Support
The SPL provides digital communication to a peripheral device, such as a computer
or PLC, in one of three modes via the communication port, terminals 26 through 32.
The mode of communication is established by the configuration of the connection
made at the SPL, RS-232, RS-485 or bipolar current loop.
The SPL utilizes simplex convention communication protocol. Data messages are
continuously transmitted at regular intervals (no poll is required) at 4800 baud. All
data is transmitted in structured messages of ASCII characters consisting of 8 data
bits, no parity, and 1 stop bit.
If Peripheral Communications (P740) is set for "formatted" messages, a comma is
inserted between each message field (except immediately preceding the "End of
Message" characters).
MT-00 Measurement Message
Field Name Definition
Start Of Message STX ($02)
Message Type
2 characters, 00 (indicates the following data pertains to a
scan point measurement)
Point #
3 characters, 001 to 003 (e.g. the message pertains to Point
Number 1)
Reading
5 characters, 0.000 to 9999. (e.g. reading = 678.9, DDDD. =
no data, EEEE. = overflow)
Status A
1 character, $0 to $F (convert to binary, e.g. temp, echo, and cable OK, not priority)
MSB LSB
# # # #
1 = temp alarm
1 = loss of echo (failsafe expired)
1 = transducer cable fault
1 = priority point
start of message point # status A status C percent
end of message temperature status B reading message type