Laurel Electronics LTM DPM SERIES ANALOG INPUT, SERIAL DATA OUTPUT - Manual (Page 31)

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20. CUSTOM ASCII PROTOCOL TRANSMITTER COMMUNICATIONS
1.0 SERIAL COMMUNICATION FORMAT
The Custom ASCII serial communication format for both RS232 and RS485 is the following:
Mode ................ Full Duplex (Separate transmit and receive lines) and Half Duplex (RS485 only)
Baud Rate ......... 300, 600, 1200, 2400, 4800, 9600, 19200 selectable with Instrument Setup
software.
Parity ................ None
Word length ...... 8 data bits
Stop bit ............ 1
2.0 MEASUREMENT DATA FORMAT
The basic measurement data format consists of 8 ASCII characters for analog input “DPM”
transmitters, such as +999.99, where is the carriage return character. The first
character is always a plus or minus sign. A decimal point is always furnished, even when it
follows the last digit.
Adding a Line Feed Character to the Basic Format
Printers and other devices that receive the data may require a line feed character following
the . The line feed character may be selected using Instrument Setup software.
Adding a Coded Data Character to the Basic Format
A coded character from A to H may be added to the data string according to the table below to
indicate the alarm and overload status of the device. If used, this character precedes the ,
so that it is the last printable character in the string. With the optional and coded
character selected, the data string will consist of 10 characters for analog input “DPM”
transmitters, such as +999.99A.
Alarm Status No Overload Overload
Neither Alarm set
Alarm 1 set only
Alarm 2 set only
Both Alarms set A
B
C
D
E
F
G
H
For example, a coded character “G” indicates that Alarm 2 only is set and that the transmitter is
in the overload condition. This information is useful when data is supplied to a computer for
listing and analysis, or when data is supplied to a Remote Display in a Master-Slave confi-
guration.