SN8P2711A
8-Bit Micro-Controller
SONiX TECHNOLOGY CO., LTD
Page 50
Version 0.1
4.4 SYSTEM HIGH CLOCK
The system high clock is from internal 16MHz oscillator RC type or external oscillator. The high clock type is controlled
by “High_Clk” code option.
High_Clk Code Option
Description
IHRC
The high clock is internal 16MHz oscillator RC type. XIN and XOUT pins are general
purpose I/O pins.
RC
The high clock is external RC type oscillator. XOUT pin is general purpose I/O pin.
32K
The high clock is external 32768Hz low speed oscillator.
12M
The high clock is external high speed oscillator. The typical frequency is 12MHz.
4M
The high clock is external oscillator. The typical frequency is 4MHz.
4.4.1 INTERNAL HIGH RC
The chip is built-in RC type internal high clock (16MHz) controlled by “IHRC_16M” coed option. In “IHRC_16M” mode,
the system clock is from internal 16MHz RC type oscillator and XIN / XOUT pins are general-purpose I/O pins.
z
IHRC:
High clock is internal 16MHz oscillator RC type. XIN/XOUT pins are general-purpose I/O pins.
4.4.2 EXTERNAL HIGH CLOCK
External high clock includes three modules (Crystal/Ceramic, RC and external clock signal). The high clock oscillator
module is controlled by High_Clk code option. The start up time of crystal/ceramic and RC type oscillator is different.
RC type oscillator’s start-up time is very short, but the crystal’s is longer. The oscillator start-up time decides reset time
length.
RC
4MHz Ceramic
4MHz Crystal
32768Hz Crystal
