4. FUNCTIONS
MELSEC-A
4-20
2) Identifier related trouble information
For module type slave stations, this stores as bit information whether or not a module is
outputting an error. The identifier related trouble information can be divided into header
and trouble information. This area stores a 2 bit value that is the identifier related trouble
information in the header, including the header (1 byte), and the device related trouble
information for this area.
Buffer memory
(2nd byte)
(4th byte)
(3rd byte)
Header
(1st byte)
Bit position
MSB
LSB
7
6
5
4
3
2
1
0
Header:
(End of device area)
Identifier area length 2 to 63 in byte units
Bits 6 and 7 are set as 01.
When this bit is 1, the 0th module has an error.
When this bit is 1, the 7th module has an error.
2nd byte
3rd byte
Bit position:
MSB
LSB
7
6
5
4
3
2
1
0
15
14
13
12
11
10
9
8