Siemens SIMATIC S5 CP 523 Manual page 199

CP 523
SEGMENT 7
3
Is data to be
sent in fixed-length
message
frames?
Yes
Calculate message frame
remainder register
Decrement message block number by 1
Yes
Last message block?
Prepare for
transfer of
last message
block
Prepare Transfer
transfer of data word
next DW to CP
Last word of the
No
message block
transferred?
Last message block?
Yes
END
EWA 4NEB 811 6044-02a
No
of the DW also the end-of-
Prepare for
transfer of
message
block
Transfer last word of the
No
No
Using the "SEND" and "Receive" Function Blocks
Transferring Send data to the CP 523
Set pointer to start of
message block
Transfer data word
to CP
Are the contents
text character?
No
No
message block
Yes
Auxiliary flag set?
Yes
END
Prepare transfer of next
DW
Yes
Set auxiliary
flag
8-9