Lpc2000

I am trying to utilize the A/D converters of the LPC2138. I have 
successfully coded a routine that utilizes AD0.0 and outputs a values 
on the serial port. The simulation works fine, but once I flash the 
program it does not work. The A/D value never changes. Any suggestions 
of where I should begin?

> I am trying to utilize the A/D converters of the LPC2138. I have
> successfully coded a routine that utilizes AD0.0 and outputs a values
> on the serial port. The simulation works fine, but once I flash the
> program it does not work. The A/D value never changes. Any suggestions
> of where I should begin?

Keep in mind the reset value of MEMMAP is 0, which is Boot Loader Mode.  

Excerpt from User manual:

"Criterion for valid user code: The reserved ARM interrupt vector location
(0x0000 0014) should contain the 2's complement of the check-sum of the
remaining interrupt vectors.  This causes the checksum of all of the vectors
together to be 0. The boot loader code disables the overlaying of the
interrupt vectors from the boot block, then checksums the interrupt vectors
in sector 0 of the flash. If the signatures match then the execution control
is transferred to the user code by loading the program counter with 0x0000
0000. Hence the user flash reset vector should contain a jump instruction to
the entry point of the user application code."

This may be cause for your troubles.


Joel