m37905 Renesas Electronics Corporation., m37905 Datasheet - Page 98

• Manufacturer Part Number: m37905
• Description: Mitsubishi 16-bit Single-chip Microcomputer 7700 Family / 7900 Series
• Manufacturer: Renesas Electronics Corporation.

Fig. 6.9.1 Processing for multiple interrupts
Time
Interrupt priority level = 3
Interrupt priority level = 5
Interrupt priority level = 2
Interrupt request
generated
Interrupt 1
Interrupt 2
Interrupt 3
Reset
Main routine
IPL = 0
I = 1
I = 0
7905 Group User’s Manual Rev.1.0
Interrupt 1
Interrupt 3
IPL = 3
IPL = 0
IPL = 2
IPL = 0
I = 1
I = 0
I = 0
I = 1
I = 0
RTI
RTI
Nesting
Interrupt 2
Interrupt 3
IPL = 5
IPL = 3
IPL : Processor interrupt priority level
The instruction in the main routine is
not executed.
I = 1
I = 0
RTI
I : Interrupt disable flag
: They are automatically executed.
: They must be set by software.
This request cannot be accepted
because its priority level is lower
than the interrupt 1’s one.
Multiple interrupts
6.9 Multiple interrupts
INTERRUPTS
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