Memobus Ascii Mode; General-Purpose Message Binary Mode - YASKAWA MP920 User Manual

Appendix B 218IF Messages
B.1.3 MEMOBUS ASCII Mode
B.1.3

MEMOBUS ASCII Mode

B.1.4

General-purpose Message Binary Mode

With ASCII communications, binary communications data is converted to ASCII before
being transmitted and received.
The following diagram shows an example of binary to ASCII conversion. As shown in the
example, 8-bit data is converted to two ASCII characters (7 bits). The example shows only
the conversion of the application data. However, in actual conversion, the EIF header is also
converted to ASCII.
7 0
07H
Length
00H
20H
MFC
03H
SFC
CPU No. 12H
00H
Reference No.
6BH
00H
No of registers
03H
In general-purpose message mode, the values for the Controller holding registers (MW reg-
isters) are set as is in the application data following the EIF header part, and data is transmit-
ted and received.
Binary Mode
Command
7 0
(L)
Contents of
MW
(H)
(L)
Contents of
MW +1
(H)
(L)
(L)
n
(H)
(H)
(L)
Contents of
MW -1
(H)
7
Length
MFC
SFC
CPU No.
Reference No.
No. of registers
n items of data from Controller holding registers MW
to MF + n-1 are set and transmitted.
There is no response to the transmission.
B-16
0
30H
37H
30H
30H
32H
30H
30H
33H
31H
32H
30H
30H
36H
42H
30H
30H
30H
33H