305
Hardware With this instruction, 8-digit BCD set values are read from a digital switch.DSW(––) utilizes 5 output bits and 8 input bits. Connect the digital switch and theInput and Output Units as shown in the diagram below. Output point 5 will beturned ON when one round of data is read, but there is no need to connect outputpoint 5 unless required for the application.
1
3
5
7
9
11
13
15
COM
0
2
4
6
8
10
12
14
COM

ID212

1
3
5
7
9
11
13
15
COM
0
2
4
6
8
10
12
14
COM
OD212
D0
D1
D2
D3
D0
D1
D2
D3
CS0
CS1
CS2
CS3
RD
D0
D1
D2
D3
D0
D1
D2
D3
CS0
CS1
CS2
CS3
RD

Interface

A7E data line

leftmost digits

To A7E chip selection

To A7E RD terminal

Leftmost digits

A7E

Rightmost digits

A7E data line rightmost digits

Input Unit

Output Unit

Note An interface to convert signals from 5 V to 24 V is

required to connect an A7E digital switch.

Advanced I/O Instructions Section 5-28