PixArt Imaging Inc.

PAC107

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PixArt Imaging Inc.

V1.4, Aug, 2005

Interrupt Priority

PAC107 has 2 level priorities. Setting / clearing a bit in the Interrupt Priority register (IP)

or Extent Interrupt Priority register (EIP) established its associated interrupt request as a

high / low priority. If a low-priority level interrupt is being serviced, a high-priority level

interrupt will interrupt it. However, an interrupt source cannot interrupt a service program

of the same or higher level. The interrupt priority is shown on Interrupt Control System

Configuration.

Interrupt Response Time

The minimum interrupt response time is eight clocks that when an interrupt request asserts

as last instruction executed. The maximum interrupt response time is 24 clocks. DJNZ

direct, rel or others instruction sets which operation period is 16 clocks, is decoded ok.

When a high priority interrupt asserts during a low priority interrupt service program, the

minimum and maximum interrupt response times are 8 clocks and 24 clocks.

OSC

Call ISR

Push PC

Ending Instructions

Interrupt Vector address

Interrupt Response Time

Interrupt Response Time

INT0 or INT1