Bradley Smoker PLC-5 user manual Point Example, Point input module, Controller memory Rack

Addressing I/O and Controller Memory 4-5

32-point Example

32-point input module

0 1

32-point I/O modules use the entire word of their group and borrow the entire word of the next group. See 1 .

Since the module is in group 0 and the inputs for group 0 and group 1 are used, you must:

install an output module in group 1 or leave the slot empty

1-slot addressing (1 I/O chassis slot = 1 I/O group = 1 input image word and 1 output image word = 16 input bits and 16 output bits.)

Controller memory

Rack x

Word #		Output Image Table
1	0
	1
	2
	3
	4
	5
	6
	7
		17	00 bits
		Input Image Table

Group 0

0 1

32-point input module

32-point output module

Word #

0

2 1

2

3

4

5

6

7

17 00 bits

Since the input image table for group 1 is unavailable because it is being used by the input module of group 0, installing a 32-point output module makes use of output image table of group 0 and 1. See 2 . You can also install 8- or 16-point output modules. But you cannot install another input module since all the input image space for groups 0 and 1 are used by the input module of group 0.

Group 0 Group 1

Publication 1785-UM012D-EN-P - July 2005