Information

© 2007 Microchip Technology Inc. DS80283E-page 7
PIC18F2585/2680/4585/4680
EXAMPLE 4:
An optimized C18 version is also provided in
Example 5. This example illustrates how it
reduces the instruction cycle count from
10 cycles to 3.
Date Codes that pertain to this issue:
All engineering and production devices.
EXAMPLE 5:
#pragma interruptlow MyLowISR
void MyLowISR(void)
{
// Handle low priority interrupts.
}
// Although MyHighISR is a high priority interrupt, use interruptlow pragma so that
// the compiler will not use retfie FAST.
#pragma interruptlow MyHighISR
void MyHighISR(void)
{
// Handle high priority interrupts.
}
#pragma code highVector=0x08
void HighVector (void)
{
_asm goto MyHighISR _endasm
}
#pragma code /* return to default code section */
#pragma code lowVector=0x18
void LowVector (void)
{
_asm goto MyLowISR _endasm
}
#pragma code /* return to default code section */
#pragma code high_vector_section=0x8
void high_vector (void)
{
_asm
CALL high_vector_branch, 1
_endasm
}
void high_vector_branch (void)
{
_asm
POP
GOTO high_isr
_endasm
}
#pragma interrupt high_isr
void high_isr (void)
{
...
}