Rockwell Automation 1746-BAS BASIC LANGUAGE - Manual (Page 201)

Publication 1746-RM001A-US-P
Input Functions 13-11
The seventh input argument is the message time-out value. This value (1 through
255) corresponds to the number of hundreds of milliseconds that are allowed to
receive the read response (0.1 through 25.5 seconds). If the read response is not
received within this time, the message aborts with the status equal to 55 in the
input file word 1, bits 0 through 7. If the time-out value is not within the range (1
through 255), the POPped status equals 2 and the transfer does not take place.
The eighth input argument is the selection of the destination file and/or string:
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0 - CPU input image file
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1 - CPU M1 file
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2 - Internal string
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3 - CPU input image file and internal string
•
4 - CPU M1 file and internal string
If you chose internal string (2), CALL 29 can be executed to initiate each data
transfer without requiring SLC processor interaction. The output file word 0, bit
10 will also initiate a string transaction.
The ninth input argument is the word offset within the destination CPU file. This
offset points to the first word transferred. The offset for the internal string is always
1 (the transaction number at location 0) followed by the data. The transaction
number is incremented upon every data transfer and wraps around from 255 to 0.
If the CPU input image file is chosen, this offset must not be 0 or 1. Zero is
reserved for data transfer handshaking bits and word 1 is reserved for the
transaction status. A 0 or 1 causes an error to be POPped (2 - bad input parameter)
and the CALL is not executed.
The tenth input argument is the string number. If the eighth input argument does
not select internal string usage, the value of this input argument is ignored but
must still be PUSHed.
The output argument is the status of the CALL. It has the following values:
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0 - Successful
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1 - Disabled
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2 - Bad input parameter
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3 - Port DH485 not enabled (DF1 enabled)
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4 - String is too small
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5 - String is not dimensioned
To disable this CALL, a 0 must be PUSHed into the first input parameter. All other
parameters are ignored but must still be PUSHed.