Analog Block Applications Using
Discrete Transfers
Chapter 5
5-2
Table 5.A
Input Image Table
Word
Bit - Decimal
(Bit - Octal)
Description
Word 0
Bits 00-15
(00-17)
Input data for channel 0.
Word 1
Bits 00-15
(00-17)
Input data for channel 1.
Word 2
Bits 00-15
(00-17)
Input data for channel 2.
Word 3
Bits 00-15
(00-17)
Input data for channel 3.
The output image table data format consists of four words. Word 0 is the
configuration word consisting of the output enable bit (OE), module mode,
scaling bit (SM), range select bits, and filter bits. SLC configuration word
is a subset of the PLC except an enable output bit is added; alarms and user
scaling are removed. Words 1 and 2 contain output data. Word 3 is
reserved.
When using the analog block modules with an SLC controller, data is
transferred as discrete data. The data is processed through a 1747-SN
remote I/O scanner module.
The following tables show the word/bit assignments for both discrete input
and output transfer.
Figure 5.2
Discrete Data Transfer Description - Output Table 1/2 Rack
Decimal
15
14
13
12
11
10
09
08
07
06
05
04
03
02
01
00
Octal
17
16
15
14
13
12
11
10
07
06
05
04
03
02
01
00
0
OE
Module Mode
SM
Range
Filter
1
Output Channel 0 Data
2
Output Channel 1 Data
3
Not used
Output Data Format