Omron CP - PROGRAMMING MANUAL 05-2007 Programming Manual page 843

Serial Communications Instructions
810
Execution Protocol Macro
condition Execution Flag
SEND(090), RECV(098), and CMND(490) also use the logical ports 0 to 7 to
execution communications sequences through Serial Communications Unit
(internally using FINS commands). PMCR(260) cannot be executed for a logi-
cal port that is already being used by SEND(090), RECV(098), CMND(490)or
PMCR(260). To prevent more than one communications sequence from being
executed for the same logical port, the corresponding Communications Port
Enable Flag (A202.00 to A202.07) should be used as a N.O. input in the exe-
cution condition for PMCR(260), as shown in the above diagram.
CJ-series Unit
CP1H
PMCR
PMCR
Internal logic ports (8 ports)
The Error Flag will turn ON in the following cases.
• The corresponding Communications Port Enable Flag is OFF for the
specified logical port (0 to 7) when PMCR(260) is executed.
• C1 is not within the specified ranges.
Designation of Receive Area
Before executing PMCR(260), users must set backup data in the receive area
for receive processing failure. Once the PMCR(260) is executed, the data in
the receive buffer is automatically stored in the receive area. One example of
the backup data application is as follows: A certain value (backup data) is set
in advance so that the present value will not be read as zero when transmis-
sion failure occurs while protocol is being executed for reading the present
value of a controller.
Communications Port
Enabled Flag
PMCR(260)
Section 3-23