HCS DAC-42A - CMD = 3, Error from DAC-4 X(A) (4 Bytes); Telegram Example CMD = 3

DAC-42(A)-x-PN
Page 43
DAC-42(A)-x-PN Manual
Revision: 1.0 22.01.2024
8.1.3 CMD = 3, Error from DAC-4x(A) (4 bytes)
Write first…
Byte Abbreviation Description
0
TADR
Telegram address, defined by the read command, Range 0..255, 0..0xFF
1
SADR
Slave address
2
ERR
Error code
3
EXCE
Exception
…Write last
ERR Error code: 0x83 = Read failed
EXCE Exception:
1 = Command not supported
2 = Wrong ID
3 = CNT== 0 or CNT > 16 (0x10)
4 = Reading of ID failed
5 = timeout slave, address wrong or not installed or
Invalid number of connected slaves
6 = Internal checksum error (Modbus)
Example for error response:
Module 3 is not installed and SADR in the master telegram is set to 3
Byte Data Abbreviation Description
0
0x23
TADR
Response telegram address
(defined by the read command)
1
0x0
1
SADR
Actual slave address
2
0x83
ERR
Error, Bit „7“ with command 0x03 is set
3
0x05
EXCE
timeout slave, address wrong or not installed
8.2 Telegram example CMD = 3
Master wants to read parameter „d1.07”:
ID = 0x0007
N = 0x01, (one parameter)
TADR = 0x24
SADR = 0x01 (always 1)
Byte Data Abbreviation
0
0x24
TADR
1
0x01
SADR
2
0x03
CMD
3
0x00
IDH
4
0x07
IDL
5
0x00
N
-
high
6
0x01
N
-
low
Response from slave (module)
CNT = 2 (2 Bytes)
DATA = 0x0133 (== 0.307A)
Byte Data Abbreviation
0
0x24
TADR
1
0x01
SADR
2
0x03
CMD
3
0x02
CNT
4
0x01
DAT1H
5
0x33
DAT1L