MC9S08SV16 Datasheet, PDF (4/40 Pages) Freescale Semiconductor, Inc – 8-Bit HCS08 Central Processor Unit (CPU)

System Clock Distribution
2 System Clock Distribution
MC9S08SV16 series use ICS module as clock sources. The ICS module can use internal or external clock
source as reference to provide up to 40 MHz CPU clock. The output of ICS module includes,
• OSCOUT— XOSC output provides EXTAL reference clock to ADC and RTC.
• ICSIRCLK — ICS internal clock reference provides clock source of RTC.
• ICSFFCLK — ICS fixed frequency clock reference (around 32.768 kHz) provides double of the
fixed lock signal to TPMs and MTIM16.
• ICSOUT — ICS CPU clock provides double of bus clock which is basic clock reference of
peripherals.
• ICSLCLK — Alternate BDC clock provides debug signal to BDC module.
The TCLK pin is an extra external clock source. When TCLK is enabled, it can provide alternate clock
source to TPMs and MTIM16. The on-chip 1 kHz clock can provide clock source of RTC and COP
modules.
TCLK
1 kHz
OSCOUT
RTC
COP
TPM2
TPM1
MTIM16
ADC
ICSIRCLK
ICSFFCLK
ICS
ICSOUT
ICSLCLK
÷2 ^{FIXED CLOCK (XCLK)}
÷2
BUS CLOCK
XOSC
EXTAL XTAL
CPU
SCI
BDC
FLASH
RAM
SPI
IIC
IPC
Figure 2. System Clock Distribution Diagram
MC9S08SV16 Series Data Sheet, Rev. 2
4
Freescale Semiconductor