mc68hc705j2 Freescale Semiconductor, Inc, mc68hc705j2 Datasheet - Page 52

• Manufacturer Part Number: mc68hc705j2
• Description: 8-bit Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

5.2.3 Software Interrupt
MOTOROLA
5-6
Either an edge-sensitive or an edge- and level-sensitive external interrupt
trigger is programmable in the mask option register. Figure 5-4 shows the
internal logic of this programmable option.
The edge- and level-sensitive trigger option allows multiple external interrupt
sources to be wire-ORed to the IRQ pin. With the level-sensitive trigger option,
an external interrupt request is latched as long as any source is holding the IRQ
pin low.
Setting the interrupt mask in the condition code register disables external
interrupts.
The software interrupt (SWI) instruction causes a nonmaskable interrupt.
IRQ
Figure 5-4. External Interrupt Trigger Option
LEVEL SENSITIVE TRIGG
V DD
(MOR OPTIO
RESETS AND INTERRUPTS
D
C
R
Q
Q
INTERRUPT MAS
EXTERNAL
INTERRUPT
REQUEST
RESET
EXTERNAL INTERRUP
BEING SERVICED
(VECTOR FETCH)
MC68HC705J2