IntrPriority (Windows Embedded CE 6.0)
1/5/2010
This global variable array provides the MIPS OAL with information about which nested interrupts are masked while the current interrupt is being handled.
Syntax
extern BYTE IntrPriority[];
Parameters
None.
Return Value
None.
Remarks
Because there is no hard-coded priority scheme in MIPS architecture, the OAL uses two structures that provide information about nested interrupts: IntrPriority and IntrMask. Both structures are part of the MIPS OAL and must be implemented by the OEM. The pIntrPrio member of the OEMGlobal structure points to the IntrPriority table.
The IntrPriority table determines, for a given combination of simultaneously pending interrupts, which interrupt is to be given the highest priority. The resulting interrupt is then serviced first.
IntrPriority contains one entry for each combination of bits in the 6-bit interrupt field. The entry defines which interrupt should be serviced. The value is the bit number multiplied by four. Multiplying the bit number by four speeds indexing into the IntrMask array in the kernel code.
For example, if interrupts 1 and 3 are both pending, IntrPriority[0xA] = 1*4 indicates that interrupt 1 should be serviced first.
Requirements
| Header | Developer Implemented |
| Windows Embedded CE | Windows CE 3.0 and later |