Rockwell Automation 1771-IE,D17716.5.7 ANAL.INPUT MOD. - Manual (Page 9)

Overview of the Analog Input Module
Chapter 2
2Ć5
Figure 2.4
Analog Input Word
17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00
0 0
Overflow/
Underflow Bit
0 = within range
1 = out of range
High Byte Low Byte
Channel
Address
(see table)
Most
Significant
Digit
(0-2)
Middle
Digit
(0-9)
Least
Significant
Digit
(0-9)
14165
Bits
16 15 14
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
Channel
Number
1
2
3
4
5
6
7
8
Channel Address Codes
Bits 00-11 These bits contain input values which range from 0 to 255
BCD (8 bit resolution).
Bits 12-13 These bits must remain reset (to 0) for proper operation.
Bits 14-16 These bits indicate by binary code which channel is being
read.
Bit 17 This bit indicates an overflow/underflow condition, and is set (to 1)
under the following conditions:
input value is zero or negative
input value is greater than or equal to 255