Rockwell Automation 1771-IR Series D RTD Input Module User Manual User Manual
Page 63
Block Transfer (Mini–PLC–2 and PLC–2/20 Processors)
D–3
Publication 1771Ć6.5.129 - March 2000
The input module transfers a specific number of words in one block
length. The number of words transferred is determined by the block
length entered in the output image table control byte corresponding
to the module’s address.
The bits in the output image table control byte (bits 00 – 05) must be
programmed to specify a binary value equal to the number of words
to be transferred.
For example, Figure D.2 shows if your input module is set up to
transfer 6 words, you would set bits 01 and 02 of the lower image
table control byte. The binary equivalent of 6 words is 000110. You
would also set bit 07 when programming the module for block
transfer read operations. Bit 06 is used when block transfer write
operations are required.
Figure D.2
SettingBlock Length (Multiple GET Instructions only)
1 0 0 0 0 1 1 0
Data Address
Contains Module
Address in BCD
Output Image Table Control
Byte Contains Read
Enable Bit and Block
Length in Binary Code
010
012
017
027
030
1
2
0
Data Table
1
R
Control
Byte
Read 6 Words
from Module
Block Transfer
Read Enable Bit
For Block
Transfer Active
Operations Only
Output Image Table
12713
Number of
Words to
Binary Bit Pattern
Lower Output Image Table Byte
Words to
Transfer
05
04
03
02
01
00
Default
0
0
0
0
0
0
1
0
0
0
0
0
1
2
0
0
0
0
1
0
3
0
0
0
0
1
1
4
0
0
0
1
0
0
5
0
0
0
1
0
1
6
0
0
0
1
1
0
:
:
18
0
1
0
0
1
0
19
0
1
0
0
1
1
Settingthe Block Length
(Multiple GET Instructions
only)