Omron SYSMAC CS1W-SCB41-V1 Operation Manual page 323

Communications Timing
Host Computer Receiving Data
Response Required
Host computer
Serial Communications
Board/Unit
Communications Port Enabled Flag
No Response Required
Host computer
Serial Communications
Board/Unit
Communications Port Enabled Flag
Response Wait Time After Host Computer Sends Data
Response Required
Host computer
Serial Communications
Board/Unit
Communications Port Enabled Flag
No Response Required
Host computer
Serial Communications
Board/Unit
Communications Port Enabled Flag
294
Command
Response
Command acknowledged
Command
Response
Command acknowledged
At (1) in the diagram, the response to a command sent from the host com-
puter is being transmitted from the port. In this case, the command transmis-
sion to the host computer is postponed until the response transmission is
completed (2).
When a response is not required from the host computer, the Communica-
tions Port Enabled Flag will turn ON when the command to the host computer
has passed from the CPU Unit to the port.
Command
Response wait time
Command acknowledged
Command
Response wait time
Command acknowledged
When response wait time has been set in the command format from the host
computer, commands to the host computer will not be transmitted until the
response time has elapsed (1). Transmission of responses to commands from
the host computer will be postponed until the command transmission to the
host computer has been completed (2).
(1) (2)
Response
Command
(2)
(1)
Command
Command completed
Response
(1) Response
Command
(2)
Response
(1) Command
(2)
Command completed
Section 9-4
Command completed
Command completed