Laurel Electronics LTM DPM SERIES ANALOG INPUT, SERIAL DATA OUTPUT - Manual (Page 30)

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Modbus ASCII Format
Byte Number
FC Action
1 2 3 4 5 6 7 8 9 10 11 12 13
03
03 Request
Response :
: MA
MA FC
FC RA
NB RA
DD*
NR
DD*
NR
LRC
LRC
CR
CR
LF
LF
04
04 Request
Response :
: MA
MA FC
FC RA
NB RA
DD*
NR
DD*
NR
LRC
LRC
CR
CR
LF
LF
05
05 Request
Response :
: MA
MA FC
FC RA
RA RA
RA WW
WW WW
WW LRC
LRC CR
CR LF
LF
08
08 Request
Response :
: MA
MA FC
FC SF
SF SF
SF WW
DD
WW
DD
LRC
LRC CR
CR LF
LF
10
10 Request
Response :
: MA
MA FC
FC RA
RA RA
RA NR
NR NR
NR NB
LRC
DD*
CR
DD*
LF
LRC CR LF
Exception
Response
: MA FC
+80
EC LRC CR LF
DD* = (DD DD) times NR (Number of Registers)
8.0 MESSAGE EXAMPLES
All examples are for Transmitter Address = 01 and No Parity.
Ser_4 ->
Addr ->
Action
Modbus RTU
010
001
Modbus ASCII
020
001
Restart Com-
munications Request
Response* 010800010000B1CB
010800010000B1CB :010800010000F6crlf
:010800010000F6crlf
Meter Reset Request
Response 01050001FF00DDFA
None
:01050001FF00FAcrlf
None
Digital Reading
** ***
Request
Response 01040003000281CB
010404000009D67C4A
:010400030002F6crlf
:010404000009D618crlf
Write Setpoint
1 = +37.00*** Request
Response 0110000100020400000E743624
01030400000E74FE74
:0110000100020400000E7466crlf
:011000010002ECcrlf
Read Setpoint
1 = +37.00*** Request
Response 01030001000295CB
01030400000E74FE74
:010300010002F9crlf
:01030400000E7476crlf
* Suggested as first message after power-up. If transmitter is in Listen-Only mode, no response
is returned. ** Example while reading +25.18 *** Decimal point is ignored.
9.0 INTERNAL REGISTERS: Please refer to the full Modbus Protocol Communications Manual,
which is downloadable from our website.