Siemens SINUMERIK 840C - Manual (Page 1064)

10.94 12 Functional Descriptions
12.28.7 Use of a high-speed data channel
12.28.7 Use of a high-speed data channel
Case 1: Write with acknowledgement,
configure high-speed data channel,
cyclical from now on:
If "New value for NC data write" is not set, enter value to be written, set "New
value for NC data write".
Case 2: Write without acknowledgement,
configure high-speed data channel,
cyclical from now on:
Set semaphores, enter value to be written, set "New value for NC data write,
enable semaphores.
Caution:
The signal "New value" must be set for the NC even though the data channel is
operating without acknowledgement. The NC reads data only if new data have
been entered in order to eliminate unnecessary link RAM access operations by the
NCK (operating time).
Case 3: Read with acknowledgement,
configure high-speed data channel,
cyclical from now on:
If "New value for NC data read" is set, read value, reset "New value for NC data
read".
Case 4: Read without acknowledgement,
configure high-speed data channel,
cyclical from now on:
If "New value for NC data read" is set, set semaphores, read value, reset "New
value for NC data read".
Enable semaphores.
Note:
"New value for NC data read" need not be evaluated at this point.
© Siemens AG 1992 All Rights Reserved 6FC5197- AA50 12–289
SINUMERIK 840C (IA)