Software Stop Mode - NEC V850/SA1 mPD703015 Preliminary User's Manual

6.4.4 Software STOP mode

(1) Settings and operating states
This mode stops the entire system by stopping the clock oscillator (generator) and by stopping the internal main
clock. The sub clock oscillator continues operating and the on-chip sub clock supply is continued. When the
FRC bit in the processor clock control register (PCC) is set (to "1"), the sub clock oscillator's on-chip feedback
resistance is cut. This sets ultra low power consumption mode during which the only current is the device's leak
current.
During this mode, program execution is stopped and the contents of all registers and on-chip RAM are retained
as they were just before software STOP mode was set. When the resonator is connected, i.e., when the CESEL
bit in the power saving control register (PSC) has been cleared (to "0"), an oscillation stabilization time is required
after the mode is canceled.
This mode can be set only when the main clock is being used as the CPU clock. This mode is set when the STP
bit in the power saving control register (PSC) has been set (to "1").
Do not set this mode when the sub clock has been selected as the CPU clock.
The operating states for software STOP mode are listed in Table 6-3.
Table 6-3. Operating States during Software STOP Mode (1/2)
Mode Settings
Item
CPU
Clock oscillator
16-bit timer (TM0)
16-bit timer (TM1)
8-bit timer (TM2)
8-bit timer (TM3)
8-bit timer (TM4)
8-bit timer (TM5)
Watch timer
Watchdog timer
Serial
SIO0-SIO2
interface
2 Note
I C
UART0,
UART1
A/D converter
DMA0-DMA2
Note µ PD703015Y and 70F3017Y only
CHAPTER 6 CLOCK GENERATION FUNCTION
When Sub Clock Exists
Stopped
Oscillation for main clock is stopped, oscillation for sub clock continues (in some cases)
Clock supply to CPU and on-chip peripheral functions is stopped
Operates when INTWTI is selected for count
clock (f is selected as count clock for watch
xt
timer)
Stopped
Stopped
Stopped
Operates when f is selected for count clock
xt
Operates when f is selected for count clock
xt
Operates when f is selected for count clock
xt
Stopped
Operates when an external clock is selected as the serial clock
Stopped
Operates when an external clock is selected as the serial clock
Stopped
Stopped
When Sub Clock Does Not Exist
Stopped
Stopped
Stopped
Stopped
141