SN8P1700
8-bit micro-controller build-in 12-bit ADC
SONiX TECHNOLOGY CO., LTD
Page 102
Revision 1.93
6
6
6
OSCILLATORS
OVERVIEW
The SN8P1700 highly performs the dual clock micro-controller system. The dual clocks are high-speed clock and
low-speed clock. The high-speed clock frequency is supplied through the external oscillator circuit. The low-speed
clock frequency is supplied through on-chip RC oscillator circuit.
The external high-speed clock and the internal low-speed clock can be system clock (Fosc). And the system clock is
divided by 4 to be the instruction cycle (Fcpu).
Fcpu = Fosc / 4
The system clock is required by the following peripheral modules:
Basic timer (T0)
Timer counter 0 (TC0)
Timer counter 1 (TC1)
Watchdog timer
Serial I/O interface (SIO)
AD converter
PWM output (PWM0, PWM1)
Buzzer output (TC0OUT, TC1OUT)
CLOCK BLOCK DIAGRAM
fl
CPUM0
LXOSC.
fcpu
fosc/4
CPUM0
fh
HXOSC.
XIN
XOUT
STPHX
HXRC
CPUM0
Divided by 4
CLKMD
Divided by 2
OSG
Divided by 2
1 : Disable
0 : Enable
OSG : Oscillator Safe Guard
1 : Disable -- System Default
0 : Enable
HXRC(1:0) is code option
•00= RC
•01 =32 Khz Oscillator
•10 = High Speed Oscillator (>10Mhz)
•11 = Standard Oscillator (4Mhz)
fl
CPUM0
LXOSC.
fl
CPUM0
LXOSC.
fcpu
fosc/4
CPUM0
fcpu
fosc/4
CPUM0
fh
HXOSC.
XIN
XOUT
STPHX
HXRC
CPUM0
fh
HXOSC.
XIN
XOUT
STPHX
HXRC
CPUM0
Divided by 4
CLKMD
Divided by 4
Divided by 4
CLKMD
Divided by 2
Divided by 2
OSG
OSG
Divided by 2
1 : Disable
0 : Enable
OSG : Oscillator Safe Guard
1 : Disable -- System Default
0 : Enable
HXRC(1:0) is code option
•00= RC
•01 =32 Khz Oscillator
•10 = High Speed Oscillator (>10Mhz)
•11 = Standard Oscillator (4Mhz)
Figure 6-1. Clock Block Diagram
HXOSC: External high-speed clock.
LXOSC: Internal low-speed clock.
OSG: Oscillator safe guard.