YASKAWA MP920 User Manual page 251

218 Header
With communications using the Extended MEMOBUS protocol, a 12-byte 218 header is
added in front of the application data. This header is automatically added or deleted by the
218IF Module the data need not be set by the application program.
7 0
Command type
Identification No.
Destination channel No.
Source channel No.
Not used
Data length (L)
(H)
Not used
Not used
• Command type
11H: MEMOBUS command
19H: MEMOBUS response
12H: General-purpose message
• Identification number
This is the required serial number transmitted to each port.
The identification number is set in the order 00H → FFH → 00H → FFH.
• Source channel number
This is the source channel number (shared memory channel number).
The number will be 00H when the channel is accessed from a device other than an MP-
series device.
• Destination channel number
Set the destination channel number (shared memory channel number).
• The number will be 00H when the channel is accessed from a device other than an MP-
series device.
• Data length
This is the total data length (number of bytes) of the 218 header and the application data.
B-3
B.1 Extended MEMOBUS Messages
B