Motorola MVME172 manual Interrupts, IndustryPack Error Reporting

4

IP2 Chip

indicates that a local bus error did occur as a consequence of a DMA operation. The contents of the local bus address counter can be examined for the address that caused the bus error.

IndustryPack Error Reporting

Each IndustryPack interface has an error pin. The error status from the four interfaces are available in the General Control Registers.

Interrupts

The IP2 chip can be programmed to interrupt the local bus master via the IPL* signal pins when one or more of the eight IndustryPack interrupts are asserted. The interrupt control registers allow each interrupt source to be level/edge sensitive and high/low true.

When the local bus master acknowledges an interrupt, if the IP2 chip determines that it is the source of the interrupt being acknowledged, it waits for IACKIN* to be asserted, then it performs an interrupt acknowledge cycle to the appropriate IndustryPack in order to obtain the vector number. It then passes the vector number on to the local bus master and asserts TA* to terminate the cycle.

When the local bus master acknowledges an interrupt, if the IP2 chip determines that it is not the source of the interrupt being acknowledged, it waits for IACKIN* to be asserted, then it passes the acknowledge on down the daisy-chain by asserting IACKOUT*.

The interrupter also provides interrupt capability for the programmable clock and for each of the four DMA controllers. Additionally, interrupts from the programmable clock can be programmed for rising and/or falling edge sensitivity. The vector passed to the local bus master during an interrupt acknowledge for the programmable clock and DMAC interrupts is from the vector base register in the IP2 chip. Part of the vector is programmable; the other part encodes the source of the interrupt.

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