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SECTION 6
VARIABLE FORMATS
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6.1.6 Outputs (Y):
Output variables are bytes which contain the data that is written to output boards at the beginning of
the main program I/O update. One 'Y' byte is allocated for each output byte, thus an S3073 16point output has two bytes allocated for it, one byte for outputs 00 thru 07 and one byte for outputs
10 thru 17. The output bytes are allocated based on the I/O slot assignments made in the system
configuration.
The format of the output byte is:
Yaab:
Where aa is the two digit slot address (00-15) and b is the byte at the slot (0 or 1).
Note: The 'Y' must be a capital letter and that the slot address must be two digits (add leading zeros
as required).
As with byte variables, individual bits within the 'Y' variable can be referenced. These bits
correspond to the respective I/O point on the output board. The form of this is:
Yaab.c: Where aa is the slot address and b is the byte address as defined above, c is the bit or
output point.
Examples: Y040, Y091, Y130.3, Y071.7, etc.
Note: Output variables can only be referenced for output boards that are actually included in the
system configuration. Any reference to output variables that do not correspond to existing output
boards will result in a compiler error.
SYSdev Program Development Manual
SYSTEMS Electronics Group
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