Yaskawa MP920 Communications Module - Manual (Page 255)

Appendix B 218IF Messages
B.1.2 MEMOBUS Binary Mode
B-6
„ Input Relay Status Read
„ Holding Register Read
MFC: 20H
SFC: 02H
Length: 07H
CPU No.
Set the command length.
Command
Always 20H.
The SFC number is 02H when the relay status is read.
Set 4 bits each for the destination CPU number and the source
CPU number.
Set the leading address of the relays to be read.
Set the number of relays to be read.
(L)
(H)
Reference No.
No. of relays (n)
(L)
(H)
(L)
(H)
7 0
MFC: 20H
SFC: 02H
Length: 03H+
CPU No.
(No.of coils/8)
(L)
(H)
(Relays 1 to 8)
Relays(No.of relays)
(L)
(H)
(L)
(H)
Set the command length.
Response
Always 20H.
The same SFC number as that specified in the command is
returned.
Set 4 bits each for the destination CPU number and the source
CPU number.
The status of the relays is returned.
7 0
MFC: 20H
SFC: 03H
Length: 07H
CPU No.
Set the command length.
Command
Always 20H.
The SFC number is 03H when the holding register contents are
read.
Set 4 bits each for the destination CPU number and the source
CPU number.
Set the leading address of the holding registers to be read.
Set the number of holding registers to be read.
(L)
(H)
Reference No.
No. of registers (n)
(L)
(H)
(L)
(H)
7 0
MFC: 20H
SFC: 03H
Length: 03H+
CPU No.
Data 1
Data n
(L)
(H)
(L)
(H)
(L)
(H)
Set the command length.
Response
Always 20H.
The same SFC number as that specified in the command is
returned.
Set 4 bits each for the destination CPU number and the source
CPU number.
The status of the read holding registers is returned.
7 0
No.of registers×2