8XC196MC, MD, MH USER’S MANUAL

Interrupt Pending or PTSSRV Bit Set

NMI

Yes

 

 

Pending

 

 

 

?

 

 

 

No

 

 

 

INT_MASK.x

No

Return

 

 

 

= 1?

 

 

 

Yes

 

 

 

PTS

No

Interrupts

No

Enabled?

 

Return

 

Enabled

 

 

 

 

 

?

 

Yes

 

Yes

 

 

 

 

PTSSEL.x

No

 

 

 

 

 

Bit = 1?

 

Priority

 

 

 

 

Yes

 

Encoder

 

 

Highest Priority Interrupt

Priority

 

 

 

 

Encoder

 

 

 

Highest Priority PTS Interrupt

Reset INT_PEND.x

Bit

Execute 1 PTS Cycle

(Microcoded)

Decrement

PTSCOUNT

No

Return PTSCOUNT

= 0?

Yes

Clear PTSSEL.x Bit

Yes PTSSRV.x No = 1?

Reset PTSSRV.x

 

 

 

Reset INT_PEND.x

Bit

 

 

 

Bit

 

 

 

 

 

 

 

 

 

 

 

 

PUSH PC

on Stack

LJMP to

ISR

Execute Interrupt

Service Routine

POP PC

from Stack

Set PTSSRV.x Bit

Return

Return

A0320-02

Figure 5-1. Flow Diagram for PTS and Standard Interrupts

5-2

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Image 89
Intel 8XC196MC, 8XC196MD, 8XC196MH manual Flow Diagram for PTS and Standard Interrupts