MC68HC705JP7CDW Freescale Semiconductor, MC68HC705JP7CDW Datasheet - Page 37

• Manufacturer Part Number: MC68HC705JP7CDW
• Description: IC MCU 8BIT 28-SOIC
• Manufacturer: Freescale Semiconductor
• Series: HC05r

Specifications of MC68HC705JP7CDW

• Core Processor: HC05
• Core Size: 8-Bit
• Speed: 2.1MHz
• Connectivity: SIO
• Peripherals: POR, Temp Sensor, WDT
• Number Of I /o: 22
• Program Memory Size: 6KB (6K x 8)
• Program Memory Type: OTP
• Ram Size: 224 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 4x12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-SOIC (7.5mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

4.5.2 PA0–PA3 Pins
Programming the PIRQ bit in the MOR to a logic 1 enables the PA0–PA3 pins (PA0:3) to serve as
additional external interrupt sources. A rising edge on a PA0:3 pin latches an external interrupt request.
After completing the current instruction, the CPU tests the IRQ latch. If the IRQ latch is set, the CPU then
tests the I bit in the condition code register and the IRQE bit in the ISCR. If the I bit is clear and the IRQE
bit is set, the CPU then begins the interrupt sequence. The CPU clears the IRQ latch while it fetches the
interrupt vector, so that another external interrupt request can be latched during the interrupt service
routine. As soon as the I bit is cleared during the return from interrupt, the CPU can recognize the new
interrupt request.
The PA0:3 pins can be edge-triggered or edge- and level-triggered. External interrupt triggering sensitivity
is selected by the LEVEL bit in the MOR.
With the edge- and level-sensitive trigger MOR option, a rising edge or a high level on a PA0:3 pin latches
an external interrupt request. The edge- and level-sensitive trigger MOR option allows connection to a
PA0:3 pin of multiple wired-OR interrupt sources. As long as any source is holding the pin high, an
external interrupt request is present, and the CPU continues to execute the interrupt service routine.
Freescale Semiconductor
IRQ/V
PA0
PA3
PA2
PA1
MASK OPTION REGISTER ($1FF1)
PP
MC68HC705JJ7 • MC68HC705JP7 Advance Information Data Sheet, Rev. 4.1
Figure 4-3. External Interrupt Logic
IRQ VECTOR FETCH
INTERNAL DATA BUS
RST
V
DD
LATCH
IRQ
R
IRQ STATUS/CONTROL REGISTER ($000D)
External Interrupts
TO BIH & BIL
INSTRUCTION
PROCESSING
V
USER EPROM
AND PEPROM
EXTERNAL
INTERRUPT
REQUEST
PP
TO
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