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Inside Macintosh: Devices /
Chapter 2 - Slot Manager / Slot Manager Reference
Data Structures

Slot Interrupt Queue Element

The Slot Manager maintains a queue of interrupt handlers for each slot. You use the SIntInstall and SIntRemove functions (described on page 2-70 and page 2-71, respectively) to install and remove routines in the queue. The SlotIntQElement data type defines a slot interrupt queue element.

TYPE SlotIntQElement =           {slot interrupt queue element}
   sqLink:        Ptr;           {pointer to next queue element}
   sqType:        Integer;       {queue type ID; must be sIQType}
   sqPrio:        Integer;       {priority value in low byte}
   sqAddr:        ProcPtr;       {interrupt handler}
   sqParm:        LongInt;       {optional A1 parameter}
Field Description
A pointer to the next queue element. This field is maintained by the Slot Manager.
The queue type identifier, which you set to the defined type sIQType.
The relative priority level of the interrupt handler. Only the low-order byte of this field is used. The high-order byte must be set to 0. Valid priority levels are 0 through 199. Priority levels 200 through 255 are reserved for Apple devices.
A pointer to the interrupt handler.
An optional value that the Slot Manager places in register A1 before calling the interrupt handler. This field is typically used to store a handle to a driver's device control entry.

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© Apple Computer, Inc.
3 JUL 1996