Cutler-Hammer D320 PLC, User Manual

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158
D320 PLC User's Manual
Instruction
Mnemonic READ Remote Intelligent I/O
Data
Range
Bit
■
Word
RMRD Read data from the shared
memory of an intelligent I/O unit
on a remote I/O drop
Double words
Ladder
Read NR1 words from remote I/O loop NN3, station
NN4, slot NN5, module memory address NR6, and
store in words starting at RR2.
Description
1. NR1: Number of words to read (number/register).
RR2: Starting address for storing read data (register).
NN3: Remote I/O network number (number).
NN4: Station number on the remote network (number).
NN5: Slot number of the intelligent I/O module to read from (number).
NR6: Starting address of the shared memory to read (number/register).
2. This instruction is used to read data from the shared memory of intelligent I/O modules
installed on remote I/O drops. Intelligent modules include the high-speed counter, analog
module, SDU module, or positioning module. Refer to the specific intelligent I/O module
user's manual for detailed instructions on using the RMRD instructions with the given
module.
3. The remote I/O network is a number from 1 to 3. The first remote I/O module in the base rack
is assigned network ID 1, the second is 2, and the third is remote I/O network 3.
4. Each intelligent I/O module on a remote I/O network may only be read from once in a given
scan. To prevent reading from a module more than once per scan, place the RMRD instruction
at the end of the program.
Example
Program Expression Operation Results
The first remote master (F8.0) is installed and there are no
initialization errors (F8.8). The communication is
completed (F8.14). Once these conditions are true, the
program reads 16 words from shared memory address 0,
slot 4, remote I/O station 5 on remote I/O network 1. This
data is written to registers starting at M0.
RMRD
To = NR1:RR2
Nt = NN3:NN4
Fr = NN5:NR6
R
NNx: number
NRx: number/register
RRx: register
RMRD
To = 16:M0
Nt = 1:5
Fr = 4:0
F8.0 F8.8 F8.14