Renesas rl78 User Manual
RL78/G1A
CHAPTER 18 STANDBY FUNCTION
(b) Release by reset signal generation
When the reset signal is generated, HALT mode is released, and then, as in the case with a normal reset
operation, the program is executed after branching to the reset vector address.
Figure 18-2. HALT Mode Release by Reset (1/2)
(1) When high-speed on-chip oscillator clock is used as CPU clock
<R>
HALT
instruction
Reset signal
High-speed on-chip
oscillator clock
Normal operation
(high-speed on-chip
oscillator clock)
HALT mode
Reset
period
Normal operation
(high-speed on-chip
oscillator clock)
Oscillates
Oscillation
stopped
Oscillates
Status of CPU
Wait for oscillation
accuracy stabilization
Note
(2) When high-speed system clock is used as CPU clock
<R>
HALT
instruction
Reset signal
High-speed
system clock
(X1 oscillation)
HALT mode
Reset
period
Oscillates
Oscillation
stopped
Oscillates
Status of CPU
Normal operation
(high-speed
system clock)
Oscillation stabilization time
(check by using OSTC register)
(check by using OSTC register)
Normal operation
(high-speed on-chip
oscillator clock)
Oscillation
stopped
Note
Starting X1 oscillation is
specified by software.
Note For the reset processing time, see CHAPTER 19 RESET FUNCTION. For the reset processing time of
the power-on-reset circuit (POR) and voltage detector (LVD), see CHAPTER 20 POWER-ON-RESET
CIRCUIT.
R01UH0305EJ0200 Rev.2.00
731
Jul 04, 2013