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Need help with Host Port Bootloader for the MotDSP56858

Started by Shahed Rahim March 3, 2005
Hi,

I have written a 2nd stage bootloader for the Host Port Interface using
polling method. And I have tested that it seems to work with the 1st stage
bootloader tester supplied with the Motorola SDK. But, if I try to boot
directly into the hardware without the SDK 1st stage bootloader, my board
does not boot properly.

It seems like I am stuck in a black box situation.

I am looking for some sample code for Host port (HI8) communication using
pollling method. I need to figure out exactly why the 1st stage bootloader
is not working.

Any help would be appreciated.

Sincerely,
Shahed Rahim


One thing you could try doing is debugging the actual boot ROM code located at 0x1f0000. Use CodeWarrior to connect to your board, then change your PC to 0x1f0000. You can use hardware breakpoints to check the code.

The boot_ROM_code.asm file in the SDK test project should be the same code that is stored in the Boot ROM. One difference with the test code project is it is using the PLL (gets initialized before calling the code in boot_ROM_code.asm), so the test code is running much faster than the boot ROM code. If your Host is not waiting for the DSP to read from the Host port prior to writing the next value, then maybe you could be getting an overrun?

> Hi,
>
>I have written a 2nd stage bootloader for the Host Port Interface using
>polling method. And I have tested that it seems to work with the 1st stage
>bootloader tester supplied with the Motorola SDK. But, if I try to boot
>directly into the hardware without the SDK 1st stage bootloader, my board
>does not boot properly.
>
>It seems like I am stuck in a black box situation.
>
>I am looking for some sample code for Host port (HI8) communication using
>pollling method. I need to figure out exactly why the 1st stage bootloader
>is not working.
>
>Any help would be appreciated.
>
>Sincerely,
>Shahed Rahim



Thanks Jeff,
Your solution worked very well. Knowing where the 1st stage bootloader
resides in memory made all the difference. I was able to debug my problem
very quickly after that.
Shahed. > Message: 6
> Date: Thu, 3 Mar 2005 11:43:45 -0500
> From: "Shahed Rahim" <>
> Subject: Need help with Host Port Bootloader for the MotDSP56858
>
> Hi,
>
> I have written a 2nd stage bootloader for the Host Port Interface using
> polling method. And I have tested that it seems to work with the 1st
stage
> bootloader tester supplied with the Motorola SDK. But, if I try to boot
> directly into the hardware without the SDK 1st stage bootloader, my board
> does not boot properly.
>
> It seems like I am stuck in a black box situation.
>
> I am looking for some sample code for Host port (HI8) communication using
> pollling method. I need to figure out exactly why the 1st stage
bootloader
> is not working.
>
> Any help would be appreciated.
>
> Sincerely,
> Shahed Rahim >
> ________________________________________________________________________
> ________________________________________________________________________
>
> Message: 7
> Date: Thu, 03 Mar 2005 12:16:30 -0500
> From:
> Subject: Re: Need help with Host Port Bootloader for the MotDSP56858
>
> One thing you could try doing is debugging the actual boot ROM code
located at 0x1f0000. Use CodeWarrior to connect to your board, then change
your PC to 0x1f0000. You can use hardware breakpoints to check the code.
>
> The boot_ROM_code.asm file in the SDK test project should be the same code
that is stored in the Boot ROM. One difference with the test code project
is it is using the PLL (gets initialized before calling the code in
boot_ROM_code.asm), so the test code is running much faster than the boot
ROM code. If your Host is not waiting for the DSP to read from the Host
port prior to writing the next value, then maybe you could be getting an
overrun?
>
> >
> >
> >
> > Hi,
> >
> >I have written a 2nd stage bootloader for the Host Port Interface using
> >polling method. And I have tested that it seems to work with the 1st
stage
> >bootloader tester supplied with the Motorola SDK. But, if I try to boot
> >directly into the hardware without the SDK 1st stage bootloader, my board
> >does not boot properly.
> >
> >It seems like I am stuck in a black box situation.
> >
> >I am looking for some sample code for Host port (HI8) communication using
> >pollling method. I need to figure out exactly why the 1st stage
bootloader
> >is not working.
> >
> >Any help would be appreciated.
> >
> >Sincerely,
> >Shahed Rahim
> >