Intel 8XC196MC, 8XC196MD, 8XC196MH manual Flow Diagram for the Ovrtm Interrupt

Models: 8XC196MD 8XC196MH 8XC196MC

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8XC196MC, MD, MH USER’S MANUAL

The interrupt service routine should read the PI_PEND (Figure 5-12 on page 5-23) register to de- termine the source of the interrupt. Before executing the return instruction, the interrupt service routine should check to see if any of the other interrupt sources are pending. Generally, PTS in- terrupt service is not useful for multiplexed interrupts because the PTS cannot readily determine the interrupt source.

Timer x

Overflows

Set OVRTMx

bit in PI_PEND

Is OVRTMx

bit set in

PI_MASK

?

Yes

Set OVRTM

bit in INT_PEND

Is OVRTM

bit set in

INT_MASK

?

Yes

Generate

OVRTM interrupt

Read PI_PEND

to see which

timer overflowed

No

No

OVRTM bit

is not set

in INT_PEND

OVRTM interrupt is not generated

A3254-01

Figure 5-3. Flow Diagram for the OVRTM Interrupt

5-8

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Intel 8XC196MC, 8XC196MD, 8XC196MH manual Flow Diagram for the Ovrtm Interrupt