Datasheet

MCU Block Diagram
MC68HC908AP Family Data Sheet, Rev. 4
Freescale Semiconductor 21
Figure 1-1. MC68HC908AP64 Block Diagram
SYSTEM INTEGRATION
MODULE
ARITHMETIC/LOGIC
UNIT (ALU)
CPU
REGISTERS
M68HC08 CPU
CONTROL AND STATUS REGISTERS — 96 BYTES
USER FLASH — (SEE TABLE)
USER RAM — (SEE TABLE)
MONITOR ROM — 959 BYTES
USER FLASH VECTOR SPACE — 48 BYTES
EXTERNAL INTERRUPT
MODULE
DDRD
PORTD
INTERNAL BUS
*
RST
*
IRQ1
COMPUTER OPERATING
PROPERLY MODULE
PTD7/KBI7 ***
PTD6/KBI6 ***
PTD5/KBI5 ***
PTD4/KBI4 ***
PTD3/KBI3 ***
PTD2/KBI2 ***
POWER-ON RESET
MODULE
POWER
PTD1/KBI1 ***
PTD0/KBI0 ***
SERIAL COMMUNICATIONS
INTERFACE MODULE 1
2-CHANNEL TIMER INTERFACE
MODULE 1
2-CHANNEL TIMER INTERFACE
MODULE 2
SERIAL PERIPHERAL
INTERFACE MODULE
KEYBOARD INTERRUPT
MODULE
10-BIT ANALOG-TO-DIGITAL
CONVERTER MODULE
ADC REFERENCE
VREFL
VREFH
DDRB
PORTB
PTB7/T2CH1
PTB6/T2CH0
PTB5/T1CH1
PTB4/T1CH0
PTB3/RxD
†
PTB2/TxD
†
PTB1/SCL
†
PTB0/SDA
†
DDRC
PORTC
PTC7/SCRxD
†
PTC6/SCTxD
†
PTC5/SPSCK
PTC4/SS
PTC3/MOSI
PTC2/MISO
PTC1
#
PTC0/IRQ2 **
#
DDRA
PORTA
PTA7/ADC7
‡
PTA6/ADC6
‡
PTA5/ADC5
‡
PTA4/ADC4
‡
PTA3/ADC3
‡
PTA2/ADC2
‡
PTA1/ADC1
‡
PTA0/ADC0
‡
LOW-VOLTAGE INHIBIT
MODULE
SERIAL COMMUNICATIONS
INTERFACE MODULE 2
(WITH INFRARED
MODULATOR/DEMODULATOR)
†
Pin is open-drain when configured as output.
‡
LED direct sink pin.
#
Pin not bonded on 42-pin SDIP.
TIMEBASE
MODULE
MULTI-MASTER IIC (SMBUS)
INTERFACE MODULE
VDDA
VDD
VSSA
VSS
VREG
** IRQ2
* Pin contains integrated pullup device.
** Pin contains configurable pullup device.
*** Pin contains integrated pullup device when configured as KBI.
CLOCK GENERATOR MODULE
OSC1
OSC2
CGMXFC
PHASE-LOCKED LOOP
X-TAL OSCILLATOR
RC OSCILLATOR
INTERNAL OSCILLATOR
OSCILLATORS AND
.
DEVICE
USER RAM
(bytes)
USER FLASH
(bytes)
MC68HC908AP64 2,048 62,368
MC68HC908AP32 2,048 32,768
MC68HC908AP16 1,024 16,384
MC68HC908AP8 1,024 8,192