HD6417021 Hitachi Semiconductor, HD6417021 Datasheet - Page 61

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

Reset State: In the reset state the CPU is reset. This occurs when the RES pin level goes low.
When the NMI pin is high, the result is a power-on reset; when it is low, a manual reset will
occur.When turning on the power, make sure to carry out a power-on reset.
42 HITACHI
or DMA address error occurs
From any state when
RES = 0 and NMI = 1
Bus request
When an interrupt source
generated
Bus release state
Bus request
Figure 2.6 Transitions Between Processing States
Power-on reset state
generated
Bus request
cleared
Bus request
Sleep mode
cleared
RES = 1,
NMI = 1
source occurs
Bus request
cleared
Bus request
generated
processing
Exception processing state
SBY bit cleared for
SLEEP instruction
Exception
Program execution state
From any state when
RES = 0 and NMI = 0
RES = 0, NMI = 0
RES = 0, NMI = 1
Exception
processing
ends
RES = 1,
NMI = 0
source occurs
Manual reset state
NMI interrupt
Standby mode
SBY bit set
for SLEEP
instruction
Power-down state
Reset states