how to remap interrupt vector - pic18f4550

[cluster]

hi

can any one tell me how to remap interrupt vector in pbp or assembly? i have written a bootloader which loads new firmware with help of external eeprom. when interrupt occurs in the new firmware it then jumps to bootloader interrupt vector and gets hang/reset. to solve this problem i need to remap interrupt vector in my bootloader
please help me

thank you

[Charles Linquis]

It depends what you mean by "remap".
If you are writing a bootloader, it is likely that you will have to deal with a variety of devices, so you will have only one interrupt level. When a PIC gets an interrupt, it jumps to location 0x08. Put a jump to whatever you want in that location.

[cluster]

It depends what you mean by "remap".
If you are writing a bootloader, it is likely that you will have to deal with a variety of devices, so you will have only one interrupt level. When a PIC gets an interrupt, it jumps to location 0x08. Put a jump to whatever you want in that location.

thanks for your reply.
but how to put jump instruction at 0x0008? i tried using this asm code but i got error "overwriting previous address content"

asm
org 0x0008
goto 0x2008
endasm

also if i am putting jump at 0x0008 then if in bootloader interrupts (usb rx interrupts) occur then it will also jump to 0x0008 and then to 0x2008?
thanks

[Charles Linquis]

It would appear that you already have an INT assigned. As a result, there is something in that location already and you are over-writing it.

ALL high priority interrupts go to 0x08. You are responsible for deciding what generated the interrupt by reading PIR(x.x and others) and doing the correct things.

[cluster]

Hi Charles,
i created this simple program and tried to run but it didn't worked. it should blink led and remap high priority interrupt vector

adcon1 = 15
DEFINE OSC 48

asm
org 0x0008
goto 0x2008
endasm

i var byte
j var byte

main:
high porta.0
for i = 0 to 254
for j = 0 to 254
high porta.0
next j
next i
for i = 0 to 254
for j = 0 to 254
low porta.0
next j
next i
goto main

but if i comment out the goto 0x2008 line it starts to blink led. since i am not using any interrupt then why its not blinking led?
can you please help me

thank you

[Charles Linquis]

I hope there is more to your program that you show. The PIC jumps to the interrupt vector location (0x08) when some peripheral (timer, serial port, etc) generates an interrupt, at which time the program counter gets reset to 0x08.

Just use Darrel's Instant Interrupts.