mc68hc908sr12 Freescale Semiconductor, Inc, mc68hc908sr12 Datasheet - Page 153

• Manufacturer Part Number: mc68hc908sr12
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

MC68HC908SR12•MC68HC08SR12 — Rev. 5.0
Freescale Semiconductor
Interrupts are latched, and arbitration is performed in the SIM at the start
of interrupt processing. The arbitration result is a constant that the CPU
uses to determine which vector to fetch. Once an interrupt is latched by
the SIM, no other interrupt can take precedence, regardless of priority,
until the latched interrupt is serviced (or the I bit is cleared).
(See
Figure
AS MANY INTERRUPTS
System Integration Module (SIM)
AS EXIST ON CHIP
9-10.)
YES
Figure 9-10. Interrupt Processing
INSTRUCTION?
INSTRUCTION?
INSTRUCTION
FROM RESET
INTERRUPT?
FETCH NEXT
INTERRUPT?
I-BIT SET?
I BIT SET?
BREAK
IRQ1
SWI
RTI
NO
NO
NO
NO
NO
YES
YES
YES
YES
LOAD PC WITH INTERRUPT VECTOR
UNSTACK CPU REGISTERS
STACK CPU REGISTERS
EXECUTE INSTRUCTION
System Integration Module (SIM)
SET I-BIT
Exception Control
Data Sheet
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