#build(reset...), missing jump at address 0 [DONE]

nilsener · Joined: 06 Dec 2005 Posts: 59

v4.014
18F2685

Bootloader
LOADER_END = 0x7FF

Hello,

after inserting

Ttelmah · Joined: 11 Mar 2010 Posts: 19504

Of course it won't.....

The build instruction, tells the compiler to build this code to run with the reset location at 0x800, and the interrupt 8 addresses above this.
Your _bootloader_, needs to be built at the bottom of memory, and contain the code, so that if it doesn't see the conditions saying 'load code', _it_ jumps to the 0x800 location. It also needs to vector the interrupt code up to the 0x808 location.

If you look at the ex_bootloader.c example, you will see that if it does not find the condition to perform a bootload (B5 pulled low), then it jumps to 'application', which is a dummy routine placed just after the loader end. Hence performing the jump to the 'real' code, once this is loaded. It also has a #int_global defined, that jumps to the required interrupt location in the main code.

Best Wishes

nilsener · Joined: 06 Dec 2005 Posts: 59

Hello Ttelmah,

thanks for quick response. I am starting to understand.

Now I get the following error:

Line 7548(1,2): Duplicate Interrupt function

if I insert the #int_global statement:

Ttelmah · Joined: 11 Mar 2010 Posts: 19504

Has your bootloader got an interrupt handler?. If so, then you will need to get more complex, and have test/branches in this....

Best Wishes

nilsener · Joined: 06 Dec 2005 Posts: 59

Hello Ttelmah,

my bootloader is not using interrupts. I have the

Ttelmah · Joined: 11 Mar 2010 Posts: 19504

No.
Get it clear what has to be where.

If your _main_ code, uses interrupts, your _bootloader_ code, must contain the code to revector the global interrupt. If your bootloader is not using interrupts, there should be no complaint from the compiler when you build _this_ with the #int_global.

Similarly, it is the bootloader code, that must contain the jump to the main code at address 0x800.

The 'main' code, is a complete program built to reside at addresses 0x800 and up, with interrupt handlers etc.. _It_ does not contain anything to connect it to the hardware vectors at the bottom of memory. This linking, is the _bootloader's_ responsibility.

So long as your booloader does not contain any interrupt calls, you can compile the _bootloader_ with the #int_global section added, without complaint.

It sounds to me as if you are trying to attach this to the main code, which already has interrupt handlers present - this _will not work_.
Again, look at the examples.

Best Wishes

nilsener · Joined: 06 Dec 2005 Posts: 59

Ok. It seems to me that the bootloader is designed to be a stand alone in the PIC and then loading the main application. What i should do is to add the bootloader to our main application (big file with more than 7000 lines) to have bootloader and main application in one file, in order to easy program it in the chip with the Promate III programmer, later. I don't want to program the bootloader first to the chip and then loading the main application as it is not suitable for production. If possible it should be done without using the #IMPORT statement to import a HEX-File into the project.

I have interrrupts in the main application and I think this is why I get the "Duplicate Interrupt function" error while inserting the #int_global statement:

Ttelmah · Joined: 11 Mar 2010 Posts: 19504

Yes,
You do not 'add' the bootloader to the main.
What you do, is build a standalone bootloader, and a standalone main. Then, use MPLAB, and load the bootloader hex file. Then load the main hex file.
This gives you an image in memory, with _both_ programs present.
You then export this.
Program using this exported file.

Best Wishes

nilsener · Joined: 06 Dec 2005 Posts: 59

OK. Is it necessary to make some #ORG modifications in the main application? I mean to #ORG the main application to LOADER_END+1 and to reserve the bootblock with #ORG 0,LOADER_END {} ? I think it must be sure that there is no address overlap from bootloader and main application?!

nilsener · Joined: 06 Dec 2005 Posts: 59

Ok, I have it, it is running. The #ORG modification makes the bootloader.h for me, I have to include it into the main application. I was completely on the wrong way by trying to make all in one file. I learned a lot in this thread, thank you very much Ttelmah, you are my hero Smile

Best regards
nilsener

Delfy_Coltech · Joined: 25 Nov 2009 Posts: 27 Location: Vietnam

Good morning,

I am studying to make bootloader for dsPIC using CCS PCD Compiler ver. 4.107.
I have a question is: What do I have to do to combine bootloader and main application all in one?

I see, we have to use #ORG, but i can't understand throughly.
Can you explain clearly? Thanks a lot! ^^
_________________
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Mechatronics Department, Coltech, VNUH
Hanoi, Vietnam.
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nilsener · Joined: 06 Dec 2005 Posts: 59

Hello,

you have to handle the bootloader and your main application as two different projects. Modify the CCS bootloader example if necessary to fit your requirements. The #org statement in the CCS bootloader example tells the compiler that the bootloader should be located into the bootblock of the PIC. Modify the addresses of the #org statement if necessary. Compile the bootloader.

Then insert the following lines in your main application after the #fuses line (path is where your bootloader is on hard disk):