Renesas RL78/G1P Hardware User Manual page 609

RL78/G1P
Example 3. Multiple interrupt servicing does not occur because interrupts are not enabled
Interrupts are not enabled during servicing of interrupt INTxx (EI instruction is not issued), therefore, interrupt request
INTyy is not acknowledged and multiple interrupt servicing does not take place. The INTyy interrupt request is held
pending, and is acknowledged following execution of one main processing instruction.
PR = 00: Specify level 0 with PR1 = 0, PR0 = 0 (higher priority level)
PR = 01: Specify level 1 with PR1 = 0, PR0 = 1
PR = 10: Specify level 2 with PR1 = 1, PR0 = 0
PR = 11: Specify level 3 with PR1 = 1, PR0 = 1 (lower priority level)
IE = 0: Interrupt request acknowledgment is disabled
IE = 1: Interrupt request acknowledgment is enabled.
R01UH0895EJ0100 Rev.1.00
Nov 29, 2019
Figure 15-10. Examples of Multiple Interrupt Servicing (2/2)
Main processing
IE = 0
EI
INTxx
(PR = 11)
IE = 1
1 instruction execution
CHAPTER 15 INTERRUPT FUNCTIONS
INTxx servicing INTyy servicing
INTyy
(PR = 00)
RETI
IE = 0
RETI
IE = 1
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