Omron SYSMAC CS Series Instruction & Reference Manual page 858

3. Instructions
Example: The following programming example shows the instructions used to constantly or periodically
execute PMCR2(264) to read data through a single receive operation.
Receive Area Not Held
Communications sequence
Receive buffer
Receive area (starting at
R+1)
Receive Area Held
Communications sequence
Receive buffer
Receive area (starting at
R+1)
Precautions
• The data in the send area specified with S is actually sent using the symbol read option, R( ), in a
send message.
• Data is actually received to the receive area specified by R using the symbol write option, W( ), in a
receive message.
• Refer to the CX-Protocol Operation Manual (W344) for procedures for designating symbols R( ) and
W( ).
• PMCR2(264) can be executed for a serial communications port on a Serial Communications Unit. Up
to 16 Serial Communications Units can be mounted to the CPU Rack and Expansion I/O Racks. The
Unit address of the communications partner must be set in bits 0 to 7 of C1 to specify which
Unit/Board is to be used and the serial port number must be set in bits 8 to 11. Unit addresses are
specified as shown in the following table.
Unit/Board
Serial Communications Unit
824
Communications
Always ON
Port Enabled Flag
Flag
Cleared
Cleared and
previous
data stored
Unit address
Unit number + 10 hex
Protocol Macro
Execution Flag
PMCR2
C1
C2
S
R
I
Set
Receive
buffer
Data that was set will be
transfer if new data is not
successfully received.
m words
Recv
Error
Cleared data
(all zeros)
stored.
Recv
Error
Set data stored if no new
data has been received
CS/CJ/NSJ Series Instructions Reference Manual (W474)