Fig. 5.5 Cancellation Of Sleep Mode By Interrupt - Fujitsu MB90420/5 (A) Series Hardware Manual

n Cancellation of sleep mode
The low-power consumption controller cancels the sleep mode at a reset input or a generation of interrupt.
• Return by a reset
At a reset, sleep mode is initialized to the main clock mode.
• Return by an interrupt
The sleep mode is cleared at an interrupt request higher than level 7 issued from resources in the sleep
mode. After the sleep mode is cleared, normal interrupt handling is performed. If the CPU is ready to
accept an interrupt by the setting of the I flag of condition cord register (CCR), interrupt level mask register
(ILM), and interrupt control register (ICR), it executes the interrupt handling. When CPU is not ready to
accept an interrupt, it executes the interrupt handling from the instruction next to the one specifying.
Figure 5.5 shows the cancellation of sleep mode by an interrupt.
CPU operation
Note: At interrupt handling, the CPU usually proceeds to the interrupt handling after executing the
instruction next to the one specifying the sleep mode. When a transition to the sleep mode is
concurrent with acceptance of the external bus hold request, the CPU may proceed to the interrupt
handling before executing the next instruction.
LOW-POWER CONSUMPTION MODE
PST pin
Stop mode
Main clock
PLL clock
CPU clock

Fig. 5.5 Cancellation of Sleep Mode by Interrupt

Oscillation stabilization wait
Stopped
Stopped
Reset sequence
Cancellation of reset
Cancellation of stop mode
5-13
Oscillating
Main clock
Processing