VIPA CPU 21 Series User Manual

Manual VIPA CPU 21x Chapter 4 Deployment of the CPU 21x-2BT10 with TCP/IP
HB103E - Rev. 05/45 4-33
If a block is called a second time in the user application before the data of
the last time is already completely send res. received, the FC block
interface reacts like this:
AG_SEND
No command is accepted until the data transfer has been acknowledged
from the partner via the connection. Until this you receive the message
"Order running" before the CP is able to receive a new command for this
connection.
AG_RECV
The order is acknowledged with the message "No data available yet" as
long as the CP has not received the receive data completely.
The following illustration shows a possible sequence for the FC blocks
together with the organizations and program blocks in the CPU cycle:
OB
Communication
connection
Communication
connection
Communication
connection
PIO write
PII read
User program
AG_SEND
AG_RECV
AG_RECV
AG_SEND
AG_SEND
AG_RECV
CPU cycle
The FC blocks with concerning communication connection are summed up
by color. Here you may also see that your user application may consist of
any number of blocks. This allows you to send or receive data (with
AG_SEND res. AG_RECV) event or program driven at any wanted point
within the CPU cycle.
You may also call the blocks for one communication connection several
times within one cycle.
FC call is faster
than CP transfer
time
AG_SEND,
AG_RECV in the
user application

VIPA CPU 21 Series Specifications

General

Brand	VIPA
Model	CPU 21 Series
Category	Control Unit
Language	English