Figure 14. daisy-chain interrupt servicing – Zilog Z08470 User Manual
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Counter/Timer Channels
Figure 14.
Daisy-Chain Interrupt Servicing
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Channel 3
Channel 2
Channel 1
Under Service
Service Suspended
Service Resumed
Service Complete
5. Second ‘RETI’ instruction issued on completion of Channel 2 Service Routine.
4. Channel 1 service routine complete, ‘RETI’ issued, Channel 2 serviced resumed.
3. Channel 1 interrupts, suspends servicing of Channel 2.
2. Channel 2 requests an interrupt and is acknowledged.
1. Priority interrupt daisy chain before any interrupt occurs.
Service Complete
Under Service
Channel 0
Highest Priority Channel