Epson S1C33L03 User Manual
5 POWER-DOWN CONTROL
A-66
EPSON
S1C33L03 PRODUCT PART
Function
Control bit
"1"
"0"
Default
System clock switch over
CLKCHG(D2)/
Power control register(0x40180)
OSC3 OSC1 OSC3
High-speed (OSC3) oscillation ON/OFF control
SOSC3(D1)/
Power control register(0x40180)
ON
OFF
ON
System clock division ratio selection
CLKDT(D[7:6])/
Power control register(0x40180)
"11" = 1/8
"10" = 1/4
"01" = 1/2
"00" = 1/1
"10" = 1/4
"01" = 1/2
"00" = 1/1
1/1
Turning off the prescaler and peripheral circuits
Current consumption can be reduced by turning off the peripheral circuits operating at high speed as much as
possible. The peripheral circuits are as follows.
1) Peripheral circuits using the clock generated by the prescaler
• 16-bit programmable timers 0 to 5 (watchdog timer)
• 8-bit programmable timers 0 to 5 (DRAM refresh, serial interface)
• A/D converter
2) Peripheral circuits using the clock (source clock for prescaler) supplied to the prescaler
• 16-bit programmable timers 0 to 5 (watchdog timer)
• 8-bit programmable timers 0 to 5 (DRAM refresh)
• A/D converter
• Serial interface
• Input/output ports
If none of all circuits of the above 1) and 2) need to be used, turn off the prescaler. If the circuit of the above
1) or 2) need to be used, do not turn off the prescaler. When operation of the prescaler is stopped, the clock
supply to the circuits of the above 2) stops. When some these circuits of the above 1) need to be used, turn off
all other unnecessary circuits and stop the clock supply from the prescaler to those circuits.
The prescaler operating control and the clock supply control bits for each peripheral circuit are shown in the
table below.
Function
Control bit
"1"
"0"
Default
Prescaler ON/OFF
PSCON(D5)/Power control register(0x40180)
ON
OFF
ON
16-bit timer 0 clock control
P16TON0(D3)/16-bit timer 0 clock control register(0x40147)
ON
OFF
OFF
16-bit timer 0 Run/Stop
PRUN0(D0)/16-bit timer 0 control register(0x48186)
RUN
STOP
STOP
16-bit timer 1 clock control
P16TON1(D3)/16-bit timer 1 clock control register(0x40148)
ON
OFF
OFF
16-bit timer 1 Run/Stop
PRUN1(D0)/16-bit timer 1 control register(0x4818E)
RUN
STOP
STOP
16-bit timer 2 clock control
P16TON2(D3)/16-bit timer 2 clock control register(0x40149)
ON
OFF
OFF
16-bit timer 2 Run/Stop
PRUN2(D0)/16-bit timer 2 control register(0x48196)
RUN
STOP
STOP
16-bit timer 3 clock control
P16TON3(D3)/16-bit timer 3 clock control register(0x4014A)
ON
OFF
OFF
16-bit timer 3 Run/Stop
PRUN3(D0)/16-bit timer 3 control register(0x4819E)
RUN
STOP
STOP
16-bit timer 4 clock control
P16TON4(D3)/16-bit timer 4 clock control register(0x4014B)
ON
OFF
OFF
16-bit timer 4 Run/Stop
PRUN4(D0)/16-bit timer 4 control register(0x481A6)
RUN
STOP
STOP
16-bit timer 5 clock control
P16TON5(D3)/16-bit timer 5 clock control register(0x4014C)
ON
OFF
OFF
16-bit timer 5 Run/Stop
PRUN5(D0)/16-bit timer 5 control register(0x481AE)
RUN
STOP
STOP
8-bit timer 0 clock control
P8TON0(D3)/8-bit timer 0/1 clock control register(0x4014D)
ON
OFF
OFF
8-bit timer 0 Run/Stop
PTRUN0(D0)/8-bit timer 0 control register(0x40160)
RUN
STOP
STOP
8-bit timer 1 clock control
P8TON1(D7)/8-bit timer 0/1 clock control register(0x4014D)
ON
OFF
OFF
8-bit timer 1 Run/Stop
PTRUN1(D0)/8-bit timer 1 control register(0x40164)
RUN
STOP
STOP
8-bit timer 2 clock control
P8TON2(D3)/8-bit timer 2/3 clock control register(0x4014E)
ON
OFF
OFF
8-bit timer 2 Run/Stop
PTRUN2(D0)/8-bit timer 2 control register(0x40168)
RUN
STOP
STOP
8-bit timer 3 clock control
P8TON3(D7)/8-bit timer 2/3 clock control register(0x4014E)
ON
OFF
OFF
8-bit timer 3 Run/Stop
PTRUN3(D0)/8-bit timer 3 control register(0x4016C)
RUN
STOP
STOP
8-bit timer 4 clock control
P8TON4(D3)/8-bit timer 4/5 clock control register(0x40145)
ON
OFF
OFF
8-bit timer 4 Run/Stop
PTRUN4(D0)/8-bit timer 4 control register(0x40174)
RUN
STOP
STOP
8-bit timer 5 clock control
P8TON5(D7)/8-bit timer 4/5 clock control register(0x40145)
ON
OFF
OFF
8-bit timer 5 Run/Stop
PTRUN5(D0)/8-bit timer 5 control register(0x40178)
RUN
STOP
STOP
A/D converter clock control
PSONAD(D3)/A/D clock control register(0x4014F)
ON
OFF
OFF
A/D conversion enable
ADE(D2)/A/D enable register(0x40244)
RUN
STOP
STOP