Plcć3 programming example – Rockwell Automation 1771-IXE/D Thermocouple/Millivolt Input Module User Manual User Manual
Page 26
3–4
Module Programming
Publication 1771Ć6.5.130 Ć May 1999
Block transfer instructions with the PLC–3 processor use one binary
file in a data table section for module location and other related data.
This is the block transfer control file. The block transfer data file
stores data that you want transferred to the module (when
programming a block transfer write) or from the module (when
programming a block transfer read). The address of the block
transfer data files are stored in the block transfer control file.
The industrial terminal prompts you to create a control file when a
block transfer instruction is being programmed. The same block
transfer control file is used for both the read and write
instructions for your module. A different block transfer control file
is required for every module.
A sample program segment with block transfer instructions is shown
in Figure 3.2, and described below.
Figure 3.2
PLC-3 Family Sample Program Structure
EN
BTR
BLOCK XFER READ
RACK:
GROUP:
MODULE:
DATA:
XXX
X
X = XXXX
XXXX:XXXX
LENGTH:
CNTL:
X
XXXX:XXXX
EN
BTW
BLOCK XFER WRITE
RACK:
GROUP:
MODULE:
DATA:
XXX
X
X = XXXX
XXXX:XXXX
DN
LENGTH:
CNTL:
X
XXXX:XXXX
Pushbutton
Power-up
Bit
Block Transfer
Read Done Bit
ER
Enable
Done
Error
12
15
13
Enable
Done
Error
02
05
03
Block Transfer
Write Done Bit
1
2
DN
ER
Program Action
At power–up, the user program examines the BTR done bit in the
block transfer read file, initiates a write block transfer to configure
the module, and then does consecutive read block transfers
continuously. The power–up bit can be examined and used anywhere
in the program.
PLCĆ3 Programming
Example