10.14.4 8 Bit Or 16 Bit Communications - Mitsubishi FX1S Series Programming Manual

FX Series Programmable Controllers
4) Interlink Mode D8120 (b12, b11, b10) = (0, 1, 0)
RS
instruction
Send data
SD (TXD)
Send request
M8122
DR(DSR)
Receive data
RD (RXD)
Time-out
evaluation
flag M8129
Receive
completion
M8123
ER(DTR)

10.14.4 8 bit or 16 bit communications.

This is toggled using the Auxiliary relay M8161. When this relay is OFF 16 bit communications
takes place. This actually means that both bytes of a 16 bit data device are used in both the
transmission and the receipt of messages. If the M8161 device is activated then 8 bit mode is
selected. In this mode only the lower 8 bits (or byte) is used to perform the transmission-
receiving actions. The toggling of the M8161 device should only occur when the RS instruction
is not active, i.e. it is OFF.
When a buffer area is specified in the RS instruction it is important to check whether 8 or 16bit
mode has been selected, i.e. a buffer area specified as D50 K3 would produce the following
results.......
16 bit mode - M8161 = OFF
Data register
D50
D51
General note regarding hardware:
Information regarding pin outs of the respective ADP special function blocks can be found
along with wiring details in the appropriate hardware manuals.
OFF ON
Data 2
ON
OFF ON
*1
Data 1
Reset using a program.
W hen it is not trurned off,the
next data cannot be received.
OFF ON
ON OFF
Reset using a program.
When it is not turned off, the next data cannot be received.
High byte Low byte
X F
0
FX
Data 4 Data 4
OFF
*1 *1
Up to 30 characfers
can be received *2
Data 3
Data 3
Time-out
evaluation time
D8129 × 10ms
*3
ON
8 bit mode - M8161 = ON
Data register
D50
D51
D52
Points Of Technique 10
FX FX
1S
1N 2N
ON
High byte Low byte
10-23
FX
2NC
F
X
0