Lpc2000

Hi,

Has any one considered "rolling their own" boot loader for the LPC2000
series?

Purpose - so that P0.14 can be released from the POR bootup
requirement.... and used for all GPIO actions.

Say for example instead of looking at P0.14 (GPIO) on POR  looking at
UART Rx incoming data...

The Philip P89V51 (80c51) series looks at the incomming UART traffic
looking for 'U' character for ~ 400mS  - then deciding weather to
execute bootload operation or jump to 0x000 (user code).

Philips offered up the bootloader hex files when there was an
improvement on the bootloader of some parts  AND a method for
uploading the bootloader.

Has anyone considered "Roll Their Own Bootloader"?

Obviously  "Rolling Your Own" can be thwart with danger.

Regards
Joe G.

Applogies if I have missed a thread that has already covered this subject.

Hi Joe,

If you are prepared to take responsibilty for your device, and not
feel intimidated by Philips advice "we do not guarantee your part if
you use your own bootloader", I have one that does this.

It appears that my release of this to the public domain may infringe
upon secrecy of undisclosed information contained in the bootloader
relating to how Philips limits the amount of on-chip RAM and ROM that
is enabled on the chip depending on what part it is suppopsed to be.

Incidentally my algorithm works better than Philips one in that it
does way with the need to specify clock speed.

Jaya

P.S. I do not believe Philips provides any guarantees whatsovever as
far as the bootloader is concerned and thus I ignore Philips advice.

--- In lpc2000@yahoogroups.com, "phlpcmicro" <joseph.goldburg@...> wrote:
>
> Hi,
> 
> Has any one considered "rolling their own" boot loader for the LPC2000
> series?
> 
> Purpose - so that P0.14 can be released from the POR bootup
> requirement.... and used for all GPIO actions.
> 
> Say for example instead of looking at P0.14 (GPIO) on POR  looking at
> UART Rx incoming data...
> 
> The Philip P89V51 (80c51) series looks at the incomming UART traffic
> looking for 'U' character for ~ 400mS  - then deciding weather to
> execute bootload operation or jump to 0x000 (user code).
> 
> Philips offered up the bootloader hex files when there was an
> improvement on the bootloader of some parts  AND a method for
> uploading the bootloader.
> 
> Has anyone considered "Roll Their Own Bootloader"?
> 
> Obviously  "Rolling Your Own" can be thwart with danger.
> 
> Regards
> Joe G.
> 
> Applogies if I have missed a thread that has already covered this
subject.
>

jayasooriah ha scritto:
> Hi Joe,
>
> If you are prepared to take responsibilty for your device, and not
> feel intimidated by Philips advice "we do not guarantee your part if
> you use your own bootloader", I have one that does this.
>   
Also I am interested to stud about this problem.
> It appears that my release of this to the public domain may infringe
> upon secrecy of undisclosed information contained in the bootloader
> relating to how Philips limits the amount of on-chip RAM and ROM that
> is enabled on the chip depending on what part it is suppopsed to be.
>   
Hmmm... I read carefully software Italy patents laws (I am italian) and 
they permits reverse engineering so I wouldn't have problems to do this.
> Incidentally my algorithm works better than Philips one in that it
> does way with the need to specify clock speed.
>
> Jaya
>
> P.S. I do not believe Philips provides any guarantees whatsovever as
> far as the bootloader is concerned and thus I ignore Philips advice.
>
> --- In lpc2000@yahoogroups.com, "phlpcmicro" <joseph.goldburg@...> wrote:
>   
>> Hi,
>>
>> Has any one considered "rolling their own" boot loader for the LPC2000
>> series?
>>
>> Purpose - so that P0.14 can be released from the POR bootup
>> requirement.... and used for all GPIO actions.
>>
>> Say for example instead of looking at P0.14 (GPIO) on POR  looking at
>> UART Rx incoming data...
>>
>> The Philip P89V51 (80c51) series looks at the incomming UART traffic
>> looking for 'U' character for ~ 400mS  - then deciding weather to
>> execute bootload operation or jump to 0x000 (user code).
>>
>> Philips offered up the bootloader hex files when there was an
>> improvement on the bootloader of some parts  AND a method for
>> uploading the bootloader.
>>
>> Has anyone considered "Roll Their Own Bootloader"?
>>
>> Obviously  "Rolling Your Own" can be thwart with danger.
>>
>> Regards
>> Joe G.
>>
>> Applogies if I have missed a thread that has already covered this
>>     
> subject.
>   
>
>
>
>
>
>
>  
> Yahoo! Groups Links
>
>
>
>  
>
>
>
>
>
>   


  ----------

No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.1.385 / Virus Database: 268.5.1/326 - Release Date: 27/04/2006


[Non-text portions of this message have been removed]

Another thing to be aware of is that some of the LPC2xxx claim
to have the bootloader in ROM rather than FLASH.

Example: LPC2101/2102/2103
 - according to the user manual block diagram

Regards,
Danish