AN-X4-ABRIO-SCAN Page
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several partial racks, mapping any one of those partial racks maps the structure for the entire rack; you
do not need to map each partial rack.
Discrete Input Data
Offset
Bit
Description
0
0
Communication Error first quarter (I/O Group 0-1)
1
Communication Error second quarter (I/O Group 2-3)
2
Communication Error third quarter (I/O Group 4-5)
3
Communication Error fourth quarter (I/O Group 6-7)
4-15
Reserved
1
0-15
Reserved (Pad for 32 bit alignment)
2-9
0-15
Discrete input data
The discrete read structure for a rack consists of 2 status words and 8 words of discrete input data.
Only bits 0 to 3 of the first word of status data are used. They consist of error bits that are set if there
is a communication error with a partial rack. Bit 0 corresponds to a rack that starts at I/O group 0, bit
1 corresponds to a rack that starts at I/O group 2, and so on.
The error bit is 1 if there’s an error scanning the rack or if the rack is inhibited, and is 0 otherwise.
Words 2-9 contain the discrete input data for the rack. Words 2 and 3 contain the data for I/O groups
0 and 1 (first ¼ rack), words 3 and 4 contain the data for I/O groups 2 and 3 (second ¼ rack), and so
on.
Refer to page 36 for information on the aliases the configuration program creates for the discrete data.
Example aliases for discrete input data, rack 0 is a quarter rack starting I/O group 0
ALIAS,"","RIO_R00_STS","Rack-00 Status","","NoName:0:I.Data[0]"
ALIAS,"","RIO_I000","Rack-00 Grp-0 Discrete Input","","NoName:0:I.Data[2]"
ALIAS,"","RIO_I001","Rack-00 Grp-1 Discrete Input","","NoName:0:I.Data[3]"
ALIAS,"","RIO_I002","Rack-00 Grp-2 Discrete Input","","NoName:0:I.Data[4]"
ALIAS,"","RIO_I003","Rack-00 Grp-3 Discrete Input","","NoName:0:I.Data[5]"
Discrete Output Data
Offset
Bit
Description
0
0
Inhibit rack that starts at first quarter (I/O Group 0-1)
1
Inhibit rack that starts at second quarter (I/O Group 2-3)
2
Inhibit rack that starts at third quarter (I/O Group 4-5)
3
Inhibit rack that starts at fourth quarter (I/O Group 6-7)
