Freescale Semiconductor HCS08 Series, Reference Manual

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Chapter 1 Device Overview
MC9S08JS16 MCU Series Reference Manual, Rev. 4
Freescale Semiconductor 19
Table 1-2 lists the functional versions of the on-chip modules.
1.3 System Clock Distribution
TCLK — External input clock source for TPM and MTIM and is referenced as TPMCLK in Chapter 14,
“Timer/Pulse-Width Modulator (S08TPMV3) .”
Figure 1-2. System Clock Distribution Diagram
The MCG supplies the following clock sources:
Table 1-2. Versions of On-Chip Modules
Module Version
Central Processing Unit (CPU) 2
Keyboard Interrupt (KBI) 2
Multi-Purpose Clock Generator (MCG) 1
Real-Time Counter (RTC) 1
Serial Communications Interface (SCI) 4
Serial Peripheral Interface (SPI16) 1
Modulo Timer (MTIM) 1
Timer Pulse-Width Modulator (TPM) 3
Universal Serial Bus (USB) 1
Cyclic Redundancy Check Generator (CRC) 2
Debug Module (DBG) 2
TPM
BDC
CPU
RAM FLASH
2
MCG
MCGOUT
÷
2
BUSCLK
MCGLCLK
MCGERCLK
COP
1
The fixed frequency clock (FFCLK) is internally synchronized to the bus clock and must not exceed one half of the
bus clock frequency.
2
Flash and EEPROM have frequency requirements for program and erase operation. See MC9S08JS16 Series
Data Sheet for details.
XOSC
EXTAL XTAL
FFCLK
1
MCGFFCLK
RTC
1 kHz
LPO
TCLK
MCGIRCLK
÷
2
USB USB RAM
SCI
ROM
MTIM
SPI
CRC