Mitsubishi Electric Q01UCPU User Manual page 389

(b) When "High-speed execution" is selected
• When switching from the scan execution type program to the interrupt/fixed scan execution type program
The CPU module does not save/restore any index register values.
• When switching from the interrupt/fixed scan execution type program to the scan execution type program
If data are written to the index register by the interrupt/fixed scan execution type program, the values of the
index register used in the scan execution type program will be corrupted.
Execution program
Index register value
Save area of index register
for scan execution
type program
*1 The Z0 value is changed to 3 in the interrupt program.
When writing data to the index register by the interrupt/fixed scan execution type program, use the ZPUSH or
ZPOP instruction to save and restore the data.
SM400
I0
SM400
(3) Processing of file register's block numbers
• When switching from the scan execution type program to the interrupt/fixed scan execution type program
The CPU module saves the file register block numbers in the scan execution type program, and passes
them to the interrupt/fixed scan execution type program.
• When switching from the interrupt/fixed scan execution type program to the scan execution type program
The CPU module restores the saved block numbers of the file register.
Scan execution
Execution program
type program
Block No. of
Block 1
file register
Save area
Switching
Scan execution
type program
Passed
Z0=1
Z0=0 Z0=0
ZPUSH
ZPOP
Switching
Passed
Saved
Block 0 Block 1
Interrupt/fixed scan
Restored
Scan execution
execution type
type program
program
Passed
*1
Z0=1 Z0=3
Z0=0 Z0=0
Data in Z0 to Z15 are
D0
stored in the area
addressed from D0.
Data in the area
D0
addressed from D0 are
stored in Z0 to Z15.
IRET
Interrupt/fixed scan
Restored
execution type
program
[RSET K0]
Block1 0
Block 1 Block 1
CHAPTER 4 DEVICES
Z0=3
Z0=0
Scan execution
type program
Block 1
Restored
Block 1
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