CHAPTER 17 STANDBY FUNCTION
362
User’s Manual U11302EJ4V0UM
(2) HALT mode release
The HALT mode can be released by the following four sources.
(a) Release by unmasked interrupt request
When an unmasked interrupt request is generated, the HALT mode is released. If interrupt request
acknowledgment is enabled, vectored interrupt servicing is carried out. If disabled, the instruction
at the next address is executed.
Figure 17-2. HALT Mode Release by Interrupt Request Generation
Remarks 1.
The broken line indicates the case when the interrupt request which has released the
standby status is acknowledged.
2.
Wait time will be as follows.
• When vectored interrupt servicing is carried out:
8 to 9 clocks
• When vectored interrupt servicing is not carried out: 2 to 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 servicing is carried out regardless of whether interrupt request acknowledgment is enabled
or disabled.
However, a non-maskable interrupt request is not generated during subsystem clock operation.
(c) Release by unmasked test input
When an unmasked test signal is input, the HALT mode is released and the instruction at the next
address to the HALT instruction is executed.
HALT
instruction
Interrupt request
Standby
release signal
Wait
Wait
HALT mode
Operating
mode
Operating mode
Clock
Oscillation
Содержание mPD780204
Страница 2: ...2 User s Manual U11302EJ4V0UM MEMO ...