Communication Using The Intelligent Function Module Device - Mitsubishi Electric MELSEC-Q Series User Manual

8 COMMUNICATION WITH INTELLIGENT FUNCTION MODULE

8.3 Communication Using The Intelligent Function Module Device

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(1) Intelligent function module device
The intelligent function module device is the buffer memory of the intelligent
function module represented as a device of Basic model QCPU program.
It enables reading data stored in the buffer memory of the intelligent function
module, or enables writing data to the buffer memory of the intelligent function
module.
For example, programming can be performed as shown below when "100" is
written to the buffer memory address 0 of the intelligent function module whose
I/O numbers are X/Y20 to X/Y2F.
(2) Difference from the FROM/TO instruction
The intelligent function module device can be handled as a device of Basic
model QCPU, enabling the processing of data read from the intelligent function
module with one instruction.
For example, programming can be performed as show below when the result of
adding the data imported from the intelligent function module and the data of D0
is stored into D2.
This saves the number of steps in the entire program.
The processing speed is the total of the instruction execution time and the access
time to/from the intelligent function modules.
POINT
When reading and processing the data of the intelligent function module frequently
in the program, use the FROM instruction to read the data at one point in the
program and store and process it in a data register, instead of using the intelligent
function module device every time.
Otherwise, the intelligent function module device accesses the intelligent function
module every time the instruction is executed, resulting in longer scan time for the
program.
REMARK
For the intelligent function module device, refer to Section 10.5.
[ ]
MOV K100 U2\G0
[ ]
+ U2\GO D0 D2
MELSEC-Q
Buffer memory address
I/O number X/Y20
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