HD6417021 Hitachi Semiconductor, HD6417021 Datasheet - Page 88

• Manufacturer Part Number: HD6417021
• Description: SuperH RISC engine
• Manufacturer: Hitachi Semiconductor

Pushes SR onto stack
Pushes PC onto stack
Copies level of accep-
Branches to exception
Notes : *1. IRQOUT is the same signal as the interrupt request signal to the CPU (Figure 5.1).
tance from I3 to I0
IRQOUT high
Reads exception
IRQOUT low
execution state
service routine
I3 to I0 : Interrupt mask bits of status register
vector table
Interrupt?
Program
*2. If the accepted interrupt is edge-sensed, the pin IRQOUT returns to the high level
NMI?
Yes
Yes
The pin IRQOUT return to the high level when the interrupt controller has accepted
the interrupt of a level higher than the I3 to I0 bits of the status register in the CPU.
when the instruction to be executed by the CPU is replaced by the interrupt
exception processing (before the status register is saved to the stack ).
If the interrupt controller has accepted another interrupt of a level higher than the
current interrupt. and has requested the interrupt to the CPU, however, the pin
IRQOUT remains low.
*1
Figure 5.2 Flowchart of Interrupt Operation
*2
User break?
No
No
Yes
Yes
interrupt?
level 14?
I3 to I0
No
Level 15
Yes
No
Yes
No
interrupt?
level 13?
I3 to I0
Level 14
No
Yes
Yes
No
interrupt?
I3 to I0 =
Level 1
level 0?
Yes
No
No
HITACHI 71