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CHAPTER 16 STANDBY FUNCTION
Preliminary User’s Manual U16035EJ1V0UM
(2) HALT mode release
The HALT mode can be released with the following three types of sources.
(a) Release by unmasked interrupt request
When an unmasked interrupt request is generated, the HALT mode is released. If interrupt acknowledge
is enabled, vectored interrupt service is carried out. If interrupt acknowledge is disabled, the next address
instruction is executed.
Figure 16-2. HALT Mode Release by Interrupt Request Generation
HALT instruction
Wait
Wait
Operation mode
HALT mode
Operation mode
Oscillation
Clock
Standby release
signal
Interrupt request
Remarks 1. The broken line indicates the case when the interrupt request which has released the standby
mode is acknowledged.
2. Wait times are as follows:
• When vectored interrupt service is carried out:
8 or 9 clocks
• When vectored interrupt service is not carried out: 2 or 3 clocks
(b) Release by non-maskable interrupt request
When a non-maskable interrupt request is generated, the HALT mode is released and vectored interrupt
service is carried out whether interrupt acknowledge is enabled or disabled.