YASKAWA MP3000 Series - Page 397

2.16 Details on Protocols
Extended MEMOBUS Protocol
2-379
Ethernet Communications
 218 Header
When communicating with the Extended MEMOBUS protocol, a 12-byte header called the 218 header is
appended before the application data. The following figure describes the elements of the 218 header.
 Extended MEMOBUS Commands
The commands that make up the Extended MEMOBUS messages are identified by function codes and
provide the functions given in the following table.
Major Function Code Sub Function Code Function
20 hex 01 hex Reads the states of coils.
02 hex Reads the states of input relays.
03 hex Reads the contents of hold registers.
04 hex Reads the contents of input registers.
05 hex Changes the state of a single coil.
06 hex Writes to a single hold register or one word.
08 hex Performs a loopback test.
09 hex Reads the contents of hold registers (extended).
0A hex Reads the contents of input registers (extended).
0B hex Writes to hold registers (extended).
0D hex Reads the contents of non-consecutive hold registers (extended).
0E hex Writes to non-consecutive hold registers (extended).
0F hex Changes the states of multiple coils.
10 hex Writes to multiple hold registers.
43 hex (extended func-
tion for accessing reg-
isters using 32-bit
addresses)
41 hex Reads the states of bits.
45 hex Changes the state of a single bit.
46 hex Writes to a single register.
49 hex Reads the contents of registers.
4B hex Writes to multiple registers.
4D hex Reads the contents of non-consecutive registers.
4E hex Writes to non-consecutive registers.
4F hex Changes the states of multiple bits.
7•••••••••0
Command type
Identification number
Destination channel number
Source channel number
Not used.
Data length (L)
Data length (H)
Not used.
Not used.
11 hex: MEMOBUS command
19 hex: MEMOBUS response
12 hex: General-purpose message
This is the serial number for the request sent to each port.
Identification numbers are set in ascending order from 00 hex and roll over after
FF hex to 00 hex.
Set the channel number of the shared memory in the destination.
The channel number is set to 00 hex if the channel is accessed by a device that
is not part of the MP Series.
This is the channel number for the source. The channel number is set to 00 hex
if the channel is accessed by a device that is not part of the MP Series.
This is the total data length of the 218 header and the application data in bytes.