Rockwell Automation 57C570 AutoMax PC3000 User Manual - Manual (Page 168)

14Ć10
Each blockĆtransfer request has these status bits, which are located
in the first word of the blockĆtransfer's status and request table:
D Block Transfer Error (bit 8)
D Block Transfer Complete (bit 9)
14.4.1 Monitoring the Block Transfer Error Bit
(Status and Control Word Bit 8)
A request's Block Transfer Error bit is set whenever an error occurs
during the blockĆtransfer. While the error bit is set, the request is
disabled. You must clear the bit and reĆinitiate the blockĆtransfer
request before the blockĆtransfer request can execute again. Make
sure to frequently monitor the error bits of your blockĆtransfer
requests.
NOTE: If a continuous blockĆtransfer request results in frequent
errors, try lengthening the update time. The target module may not
be able to accept a request as fast as it is being sent.
14.4.2 Monitoring the Block Transfer Complete Bit
(Status and Control Word Bit 9)
A request's Block Transfer Complete bit is set whenever a
blockĆtransfer has been completed.
If the blockĆtransfer is: Then:
continuous the complete bit is set (1) when the first transfer has
been completed
It then remains on until you clear it via your
application program. Once you clear the bit, it is set
after the next request is complete.
If your application needs to know each time the block
transfer is updated, you should clear this bit each
time, so the program can determine when the bit gets
set again.
nonĆcontinuous the complete bit is set (1) when the request is finished
You must reĆinitialize the block transfer request for it to
be able to execute when the logic conditions next
dictate it.
If your application needs to know each time the block
transfer is updated, you should clear this bit each
time, so the program can determine when the bit gets
set again.