MC68HC908QY4_10 Datasheet, PDF (74/168 Pages) Freescale Semiconductor, Inc – M68HC08 Microcontrollers

External Interrupt (IRQ)
PTA0/AD0/TCH0/KBI0
PTA1/AD1/TCH1/KBI1
PTA2/IRQ/KBI2/TCLK
PTA3/RST/KBI3
PTA4/OSC2/AD2/KBI4
PTA5/OSC1/AD3/KBI5
PTB0
PTB1
PTB2
PTB3
PTB4
PTB5
PTB6
PTB7
8-BIT ADC
128 BYTES RAM
V_DD
POWER SUPPLY
V_SS
M68HC08 CPU
MC68HC908QY4 AND MC68HC908QT4
4096 BYTES
MC68HC908QY2, MC68HC908QY1,
MC68HC908QT2, AND MC68HC908QT1:
1536 BYTES
USER FLASH
CLOCK
GENERATOR
(OSCILLATOR)
SYSTEM INTEGRATION
MODULE
SINGLE INTERRUPT
MODULE
BREAK
MODULE
POWER-ON RESET
MODULE
KEYBOARD INTERRUPT
MODULE
16-BIT TIMER
MODULE
COP
MODULE
MONITOR ROM
RST, IRQ: Pins have internal (about 30K Ohms) pull up
PTA[0:5]: High current sink and source capability
PTA[0:5]: Pins have programmable keyboard interrupt and pull up
PTB[0:7]: Not available on 8-pin devices – MC68HC908QT1, MC68HC908QT2, and MC68HC908QT4 (see note in
12.1 Introduction)
ADC: Not available on the MC68HC908QY1 and MC68HC908QT1
Figure 8-1. Block Diagram Highlighting IRQ Block and Pins
When set, the IMASK bit in INTSCR masks the IRQ interrupt request. A latched interrupt request is not
presented to the interrupt priority logic unless IMASK is clear.
NOTE
The interrupt mask (I) in the condition code register (CCR) masks all
interrupt requests, including the IRQ interrupt request.
A falling edge on the IRQ pin can latch an interrupt request into the IRQ latch. An IRQ vector fetch,
software clear, or reset clears the IRQ latch.
MC68HC908QY/QT Family Data Sheet, Rev. 6
74
Freescale Semiconductor