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Interrupt

Syntax

Interrupt = vector

Description

Specifies the interrupt (IRQ) shared by all of the AG boards on the ISA bus. This statement may only be used in a Common section, outside the context of a specific board.

There are no interrupt selection jumpers on AG boards; the selection is configured with agmon. Allowable values are 5, 7, 9, 10, 11, 12, and 15.

Note: The sample AG configuration files provided with CT Access set the interrupt to 7, because this works on most machines. IRQ 7 is the lowest priority interrupt. In a heavily loaded system, this could cause the AG boards to be starved for service. In these systems, one of the higher numbered interrupts should be used. See Section 1.3.2, Interrupts for more details on configuring interrupts.

The Interrupt statement is mandatory for ISA boards. The statement is ignored by AG boards on the PCI bus.
For AG boards on the PCI bus, the system chooses which interrupt is used. The system BIOS for every computer system which supports a combination of PCI slots and ISA slots provides some mechanism for assigning interrupts to either the ISA slots or to the PCI and plug -n-play slots.

It is critical that all interrupts which are assigned to the PCI slots are not used by any ISA boards.

If an AG board on the ISA bus uses the interrupt assigned to the PCI board, agmon fails to initialize an AG PCI board. The board locate utility, blocate, correctly identifies the PCI board, regardless of interrupt conflicts.

Note: If you accidentally initialize an ISA board in your system with an interrupt that was allocated for the PCI bus, modify the Interrupt keyword in the AG configuration file and reboot your system.

Alias: IRQ

Example

Interrupt = 7

See Also

Address


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