Functional Blocks

The write post bus error interrupter is an edge-sensitive interrupter connected to the local bus to VMEbus write post bus error signal line.

The VMEbus IRQ1 edge-sensitive interrupter is an edge-sensitive interrupter connected to the VMEbus IRQ1 signal line. This interrupter is used when one of the tick timers is connected to the IRQ1 signal line. When this interrupt is acknowledged, the vector is provided by the VMEchip2 and a VMEbus interrupt acknowledge is not generated. When this interrupt is enabled, the VMEbus IRQ1 level-sensitive interrupter should be disabled.

The VMEchip2 VMEbus interrupter acknowledge interrupter is an edge- sensitive interrupter connected to the acknowledge output of the VMEbus interrupter. An interrupt is generated when an interrupt on the VMEbus from VMEchip2 is acknowledged by a VMEbus interrupt handler.

The tick timer interrupters are edge-sensitive interrupters connected to the output of the tick timers.

The DMAC interrupter is an edge-sensitive interrupter connected to the DMAC.

The GCSR SIG3-0 interrupters are edge-sensitive interrupters connected to the output of the signal bits in the GCSR.

The location monitor interrupters are edge-sensitive interrupters connected to the location monitor bits in the GCSR.

The software 7-0 interrupters can be set by software to generate interrupts.

The VMEbus IRQ7-1 interrupters are level-sensitive interrupters connected to the VMEbus IRQ7-1 signal lines.

The interrupt handler provides all logic necessary to identify and handle all local interrupts as well as VMEbus interrupts. When a local interrupt is acknowledged, a unique vector is provided by the chip. Edge-sensitive interrupters are not cleared during the interrupt acknowledge cycle and must by reset by software as required. If the interrupt source is the VMEbus, the interrupt handler instructs the VMEbus master to execute a VMEbus IACK cycle to obtain the vector from the VMEbus interrupter. The chip connects to all signals that a VMEbus handler is required to drive

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Motorola MVME172 manual Functional Blocks