Renesas rl78 User Manual
RL78/G1A
CHAPTER 18 STANDBY FUNCTION
(2) HALT mode release
The HALT mode can be released by the following two sources.
(a) Release by unmasked interrupt request
When an unmasked interrupt request is generated, the HALT mode is released. If interrupt acknowledgment is
enabled, vectored interrupt servicing is carried out. If interrupt acknowledgment is disabled, the next address
instruction is executed.
Figure 18-1. HALT Mode Release by Interrupt Request Generation
HALT
instruction
Operating mode
HALT mode
Operating mode
Oscillation
High-speed system clock,
High-speed on-chip oscillator clock,
or subsystem clock
Status of CPU
Standby
release signal
Note 1
Interrupt
request
Wait
Note 2
Notes 1.
For details of the standby release signal, see Figure 16-1.
2.
Wait time for HALT mode release
• When vectored interrupt servicing is carried out
• When vectored interrupt servicing is carried out
Main system clock:
15 to 16 clock
Subsystem clock (RTCLPC = 0): 10 to 11 clock
Subsystem clock (RTCLPC = 1): 11 to 12 clock
• When vectored interrupt servicing is not carried out
• When vectored interrupt servicing is not carried out
Main system clock:
9 to 10 clock
Subsystem clock (RTCLPC = 0):
4 to 5 clock
Subsystem clock (RTCLPC = 1):
5 to 6 clock
Remark The broken lines indicate the case when the interrupt request which has released the standby mode is
acknowledged.
R01UH0305EJ0200 Rev.2.00
730
Jul 04, 2013