[En-Nut-Discussion] eboot - bootloader under 4k

[Don Ingram]

Bernard Fouché wrote:
> FYI a while back I did change appload. Now I have a version that:
> 
> - fits under 4k (4068 bytes with gcc 3.4.5 and avr-libc 1.4.5)
> - has a .bss segment and a .data segment as usual apps (however .data is 
> unused at the moment)
> - flash only modified pages from a boot to another, sparing flash write 
> cycles when rebooting often. If you reboot and get the same file, no 
> flashing is done.
> - read jumpers on port F to select if network info from EEPROM is to be 
> read before booting and to select if network bootloading is to be done. 
> That allows you to bootload once and then keep your current application 
> if it has to be used in a place you can't bootload.
> - be able to read and flash a usual binary file or use files that have 
> CRC's prefixed at the beginning of the file thanks to an external C 
> tool. ('addcrc'). This is to be sure that you flash a correct file (not 
> relying on UDP checksums)


> - be aware of gateway issues (you can TFTP from a remote site if your 
> firewall correctly manages TFTP)

This I would love to see. I hacked appload to save some space to allow for 
variants to be specified via EEPROM but the code still requires a local TFTP 
server which is a bit of an inconvenient issue in my current application.

Similarly dealing with CRC'd files would be great.



-- 
Cheers

Don
> 
> I sent this to Harald a long time ago but I guess he did not get enough 
> time to have a look. I just had a look recently, adding the jumper thing 
> and sparing a few more bytes. If someone is interested, I can post it 
> there and if these modifications are considered usefull, one may include 
> them in NutOs.
> 
>  Bernard
> 
> Thiago A. Corrêa wrote:
>> Hi guys,
>>
>>    Ever since last year
>> (http://www.egnite.de/pipermail/en-nut-discussion/2005-May/004446.html)
>> eboot wasn't compiling under somewhat recent gcc versions. Today I
>> gave it a try to optimize a bit of the space based on the code from
>> appload. The only problem is that my SP Duo died. I don't know when I
>> will have one again since its currently sold out at Embedded
>> creations.
>>
>>   So, anyway, if someone could check it out it would be great. I have
>> attached a patch based on current CVS then I can commit it if it's
>> reported to work.
>>
>>    There are still other places where the same optimizations can be
>> applied further reducing the size.
>>
>> Regards,
>>     Thiago A. Correa
>> _______________________________________________