YASKAWA MP3000 Series - Page 423

2.16 Details on Protocols
MEMOBUS Protocol
2-405
Ethernet Communications
 Reading the Contents of Hold Registers
 Reading the Contents of Input Registers
7•••••••••0
(H)
(L)
(H)
(L)
CRC-16
(H)
(L)
Command
Slave address
Function code: 03 hex
First address
Number of registers
The function code to read the contents of hold registers is 03 hex.
Set the first address of the hold registers to read.
Set the number of hold registers to read.
Error checking
7•••••••••0
CRC-16
(H)
(L)
(H)
(L)
(H)
(L)
(H)
(L)
Response
Slave address
Function code: 03 hex
Number of data items
Contents of the
first hold register
Contents of the
next hold register
Contents of the
next hold register
The function code to read the contents of hold registers is 03 hex.
This contains the length of the data item that was read in bytes.
This contains the contents of the first data item that was read.
Error checking
7•••••••••0
(H)
(L)
(H)
(L)
CRC-16
(H)
(L)
Command
Slave address
Function code: 04 hex
First address
Number of registers
The function code to read the contents of input registers is 04 hex.
Set the first address of the input registers to read.
Set the number of input registers to read.
Error checking
7•••••••••0
CRC-16
(H)
(L)
(H)
(L)
(H)
(L)
(H)
(L)
Response
Slave address
Function code: 04 hex
Number of data items
Contents of the
first input register
Contents of the
next input register
Contents of the
next input register
The function code to read the contents of input registers is 04 hex.
This contains the length of the data item that was read in bytes.
This contains the contents of the first data item that was read.
Error checking