Lpc2000

> Is it true that Phillips ISP does the checksum calculation before
> programming the vector code into flash?

> I notice the .hex files that I'm making (using IAR's software) 
> doesn't contain the calculated checksum (0x14)for the vector code. 
> It's usually filled with 0's (without the fill option).

> Is there's a way for me to generate the vector checksum in the 0x14 
> space of the hex file?

Leighton,

This is what I do.

The vector table for the processor (The first 32 bytes of memory)
normally has branches to the routines. Since routine addresses change
as code is changed, the checksum changes.

I created a table of seven addresses located immediately after the
vector table. These seven addresses are the start addresses for reset
and the interrupts. The branch instructions of the interrupt vector
table were replaced with a load PC instruction pointing to the
appropriate address.

The hex file will then have the checksum. My startup code below:

@---------------------------------------------------------------------------
@ Interrupt vectors
@---------------------------------------------------------------------------
intvect:

        LDR     pc, startaddr
        LDR     pc, undefinstaddr
        LDR     pc, softintaddr
        LDR     pc, preabortaddr
        LDR     pc, dataabortaddr
        .word   0xb8a06f60
        LDR     pc, interruptaddr
        LDR     pc, fastintaddr

startaddr:
        .word   start

undefinstaddr:
        .word   undefined_instruction_routine

softintaddr:
        .word   software_interrupt_routine

preabortaddr:
        .word   prefetch_abort_routine

dataabortaddr:
        .word   data_abort_routine

interruptaddr:
        .word   interrupt_routine

fastintaddr:
        .word   fast_interrupt_routine


@---------------------------------------------------------------------------
@ Start up code
@---------------------------------------------------------------------------

start:

 <code...>