Datasheet

General Description
MC68HC908LJ12 — Rev. 2.1 Technical Data
Freescale Semiconductor General Description 37
Figure 1-1. MC68HC908LJ12 Block Diagram
SYSTEM INTEGRATION
MODULE
ARITHMETIC/LOGIC
UNIT (ALU)
CPU
REGISTERS
M68HC08 CPU
CONTROL AND STATUS REGISTERS — 96 BYTES
USER FLASH — 12,288 BYTES
USER RAM — 512 BYTES
MONITOR ROM — 960 BYTES
USER FLASH VECTOR SPACE — 48 BYTES
EXTERNAL INTERRUPT
MODULE
DDRD
PORTD
INTERNAL BUS
* RST
* IRQ
COMPUTER OPERATING
PROPERLY MODULE
PTD7/KBI7**
PTD6/KBI6**
PTD5/KBI5**
PTD4/KBI4**
PTD3/SPSCK
PTD2/MOSI
POWER-ON RESET
MODULE
POWER
VSS
VDDA
PTD1/MISO
PTD0/SS
REAL TIME CLOCK
MODULE
2-CHANNEL TIMER INTERFACE
MODULE 1
2-CHANNEL TIMER INTERFACE
MODULE 2
LIQUID CRYSTAL DISPLAY
DRIVER MODULE
SERIAL PERIPHERAL
INTERFACE MODULE
KEYBOARD INTERRUPT
MODULE
10-BIT ANALOG-TO-DIGITAL
CONVERTER MODULE
CLOCK GENERATOR MODULE
OSC1
OSC2
CGMXFC
32.768-kHz OSCILLATOR
PHASE-LOCKED LOOP
FP0/BP3
VDD
ADC REFERENCE
VREFL
VREFH
DDRB
PORTB
PTB7/ADC5
PTB6/ADC4
PTB5/T2CH1
‡
PTB4/T2CH0
‡
PTB3/T1CH1
‡
PTB2/T1CH0
‡
PTB1/RxD
†
PTB0/TxD
†
DDRC
PORTC
PTC7/FP26
PTC6/FP25
PTC5/FP24
PTC4/FP23
PTC3/FP22
PTC2/FP21
PTC1/FP20
PTC0/FP19
DDRA
PORTA
PTA7/ADC3
PTA6/ADC2
PTA5/ADC1
PTA4/ADC0
PTA3/KBI3**
PTA2/KBI2**
PTA1/KBI1**
PTA0/KBI0**
LOW-VOLTAGE INHIBIT
MODULE
FP1–FP18
BP0–BP2
* Pin contains integrated pullup device.
** Pin contains integrated pullup device if configured as KBI.
†
High current sink pin, 15mA.
‡
High current sink pin, 8mA.
SERIAL COMMUNICATIONS
INTERFACE MODULE
(WITH INFRARED
ENCODER/DECODER)
#
#
# Pins available on 64-pin packages only.