Laurel Electronics Custom ASCII Protocol For Laureate Series 2 Digital Panel Meters, Counters, Timers & L-Series Transmitters User Manual
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7. CUSTOM ASCII COMMUNICATION PROTOCOL
7.1 SERIAL COMMUNICATION FORMAT
The Custom ASCII serial communication format for RS232, RS485 and USB is the following:
Duplex ...................... Full duplex for RS232 & RS485. Half duplex selectable for RS485.
Baud Rate ................. 300, 600, 1200, 2400, 4800, 9600, 19200 selectable by front panel Menu
item “Ser 1”, Sub-menu item “Digit 4” for DPM, "Digit 5" for counter.
Parity ........................ None
Word length .............. 8 data bits
Stop bit .................... 1
7.2 MEASUREMENT DATA FORMAT
The basic measurement data format consists of 8 ASCII characters for the DPM, such as
is the space character and
space character 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 measure-
ment data may require a line feed character
following the
selected in “Ser 2”.
Adding a Coded Data Character to the Basic Format
It is possible to add a coded character from A to h to
the data string according to the table to the right to
indicate the alarm and overload status of the device.
If used, this character precedes the
last printable character in the string. With the
optional
string will consist of 10 characters for the DPM:
counter:
For example, a coded character “G” indicates that
Alarm 2 only is set and that the DPM is in 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 configuration.
Alarm #
4 3 2 1
Alarm with
No Overload
Alarm with
Overload
0 0 0 0
0 0 0 1
0 0 1 0
0 0 1 1
A
B
C
D
E
F
G
H
0 1 0 0
0 1 0 1
0 1 1 0
0 1 1 1
I
J
K
L
M
N
O
P
1 0 0 0
1 0 0 1
1 0 1 0
1 0 1 1
Q
R
S
T
U
V
W
X
1 1 0 0
1 1 0 1
1 1 1 0
1 1 1 1
a
b
c
d
e
f
g
h