Rockwell Automation 1747-BSN Backup Scanner Module - Manual (Page 127)

Publication 1747-UM010B-EN-P - September 2003
RIO Block Transfer 7-15
Transmitted Word Count/Error Code, Word 2 (DLEN)
Transmitted Word Count is the status of the actual number of BTW
words sent or the number of BTR words received. The processor uses
this number to verify the transfer. This number should match the
requested word count (unless the transmitted word count is zero). If
these numbers do not match, the processor sets the ER bit (bit 12). If
there is an error, the processor gives the error code in Word 2 of the
control structure in the form of a negative number. See Table 7.3,
“BTR/BTW Error Codes,” for a list of error codes. Only one error code
is stored at a time (a new error code overwrites the previous error
code).
Table 7.3 BTR/BTW Error Codes
Error Code Description
0 The block transfer completed successfully.
-6 Illegal block transfer length requested.
-7 Block transfer communication error occurred when block transfer
request was initiated.
-8 Error in block transfer protocol.
-9 Block Transfer Time-out - Either the SLC user program cancelled the
block transfer or the scanner’s block transfer timer timed out. Note
that a time-out error occurs if a block transfer is attempted at a
location that is not configured for block transfer operation (e.g.,
requesting a block transfer for a location that is an output module).
-10 No RIO channel configured.
-11 Attempted a block transfer either to a non-configured block transfer
device (i.e., an invalid logical rack, group, or slot), or at a
complementary device location where there is no corresponding
primary image space allocated.
-12 Attempted a block transfer to an inhibited device.