checksum related doubts

[isotopus]

Until now, I have been working with PIC16F, and I've managed "checksum" with directive #id. this way, I may store a fixed version to any code that I have compiled.

But now I have just started working with PIC18F4510, and I have the following problem. I try the same instruction that before:

#id VERSION_01, VERSION_02,VERSION_03,VERSION_04

But now, when I compile any source code change, MPLAB IDE "checksum" field changes, although VERSION_0X macros have not changed.

I have also tried with:

#rom 0x20000={VERSION_ID0, VERSION_ID1, VERSION_ID2, VERSION_ID3, VERSION_ID4, VERSION_ID5, VERSION_ID6, VERSION_ID7}

But the same problem....


Sorry because of my ignorance about the checksum calculation, but I'm a beginner... Does anyone know how does MPLAB generate the checksum (which data is used)??

Could somebody help me please?

Thank you very much!!

[Neutone]

So you wish to have a checksum for the HEX file match your program version? I suppose if you have a macro that edits a few bytes of program memory to the right value this could be achieved. I have never heard of this being done before.

Whats your macro look like?

[Guest]

Thanks for your reply Neutone !

An example of macro used until now (PIC16F):

#define VERSION_ID0 0
#define VERSION_ID1 1
#define VERSION_ID2 2
#define VERSION_ID2 3

#id VERSION_ID0, VERSION_ID1, VERSION_ID2, VERSION_ID3

With the PIC18F4510 I have tried the same and as it doesn't seem to work I have used as well:

#rom 0x20000={VERSION_ID0, VERSION_ID1, VERSION_ID2, VERSION_ID3, VERSION_ID4, VERSION_ID5, VERSION_ID6, VERSION_ID7}

What do you think about it ? Have you got any other idea ?

Thanks for your help !!

[Ttelmah]

Yes.
One very simple comment. :-)
How many 'zeros' should there be in the ROM address for the ID bytes?.

Best Wishes

[Guest]

Hi and Thanks again !!

Yes, I know that I must put #rom 0x200000 (One more zero )...but it does not work as well...

I do not know what more can I do...

As people say in my country " I see phantoms everywhere with this stuff..."

Thanks...