Rockwell Automation 1771-TCM,D17716.5.108 TEMPERATURE CONTROL MOD - Manual (Page 32)

Communicating with Your Module
Chapter 3
3-10
BlockĆTransfer Read
You can generate all block-transfer reads from your 1771-TCM module
thru a single block-transfer read instruction. Enter the block length as 64
words. Write your ladder logic so that when you receive a block of data in
the 64-word block addressed by the block-transfer read instruction, you
first read the block identification code at the beginning of the block and
then based on the ID, send the block of data to the appropriate address for
that particular type of block
System Satus Block
64 words
Calibration Read Block
14 words
64Ćword block
addressed by the
blockĆtransfer
read instruction
Gains Block
57 words
1771ĆTCM Module PLC Data Table
BlockĆtransfer Read
Step 2 Ċ
You read the block ID from
the data in the 64Ćword bloc
addressed by the BTW
instruction, and based on the
ID, send the block of data to
the appropriate address for
that particular type of block.
Step 1 Ċ
You first use the
BTR instruction to
bring the block of
data from the
module.
In the dynamic block that you send to the module, you specify whether the
module should send back a gains block or a system status block in
subsequent block-transfer reads.