Mitsubishi QD51, User Manual

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MELSEC-Q
4 ABOUT QD51 (-R24) FUNCTIONS
4.8 Data Communications Between Tasks
During multitask processing, the content of variables or arrays in each task, etc. can
only be referred to in each respective BASIC program.
For exchange of data between BASIC programs during multitask processing, use the
following.
1) Expansion Relay (EM) : ON/OFF Data
2) Expansion Register (ED) : Data
3) Common Memory
: Data
4.8.1 ON/OFF data communications by expansion relay (EM)
The QD51 (-R24)'s expansion relay (EM) is a device which can perform ON/OFF
control and read the ON/OFF status from all tasks.
(For details of the expansion relay, refer to Section 3.5.6.)
Expansion relay
(EM0 to EM1023)
Program 1 Program 2
Reading of the
ON/OFF state
Reading of the
ON/OFF state
ON/OFF
control
ON/OFF control
The expansion relays that can be used by the QD51 (-R24) are EM0 to EM1023, 1024
points.
[Commands and functions used]
Commands and functions that perform ON/OFF data communications by the
expansion relay are shown below.
Command, Function Name Processing Contents
B@ : Performs expansion relay ON/OFF control and reading of the
ON/OFF status.