Datasheet

MC68HC908KX8 • MC68HC908KX2 • MC68HC08KX8 Data Sheet, Rev. 2.1
Freescale Semiconductor 19
MCU Block Diagram
Figure 1-1. MC68HC908KX8 MCU Block Diagram
COMPUTER OPERATING PROPERLY
MODULE
SECURITY
MODULE
ARITHMETIC/LOGIC
UNIT
CPU
REGISTERS
M68HC08 CPU
CONTROL AND STATUS REGISTERS — 78 BYTES
USER FLASH — 7680 BYTES
USER RAM — 192 BYTES
MONITOR ROM — 295 BYTES
USER FLASH VECTOR SPACE — 36 BYTES
POWER
INTERNAL BUS
V
DD
V
SS
PTA
DDRA
POWER-ON RESET
MODULE
LOW-VOLTAGE INHIBIT
MODULE
PTA4/KBD4
(2), (3)
PTA3/KBD3/TCH1
(2), (3)
PTA2/KBD2/TCH0
(2), (3)
PTA1/KBD1
(2), (3)
PTA0/KBD0
(2), (3)
IRQ1
(1)
2-CHANNEL TIMER INTERFACE
MODULE
PTB
DDRB
PTB7/(OSC2)/RST
(4)
PTB5/TxD
PTB4/RxD
PTB3/AD3
PTB2/AD2
PTB0/AD0
PTB1/AD1
KEYBOARD INTERRUPT
MODULE
ANALOG-TO-DIGITAL CONVERTER
MODULE
SERIAL COMMUNICATION INTERFACE
MODULE
PROGRAMMABLE TIME BASE
MODULE
PTB6/(OSC1)
(4)
FLASH BURN-IN ROM — 1024 BYTES
INTERNAL CLOCK GENERATOR
MODULE
SYSTEM INTEGRATION
MODULE
IRQ
MODULE
(SOFTWARE SELECTABLE)
Notes:
1. Pin contains integrated pullup resistor
2. High-current source/sink pin
3. Pin contains software selectable pullup resistor if general function I/O pin is configured as input.
BREAK
MODULE