Tiny Bootloader for PIC micros...

[Najim]

Hi all,

Well here it is my first post in this forum.

I would like to program a PIC 18F4525 with the tiny bootloader wich seems to be very flexible,small and fast.
The problem is that with this micro we are supposed to make a modification in the bootloader code... but don t know which one...

If someone knows how to do it, it would help me a lot...

Have fun guys.
Najim.

[Najim]

Hey guys I found the solution to make tinybootloader work with the pic 18F4525...
Actually it works fine without any modification The thing is that the watch dog timer has to be disabled in orther to not reset the pic when the bootloader is working...

Hope it will help someone.

Najim.

[justDIY]

Hi Najim, and welcome to the boards.

Tinybld is great isn't it?  I mean, 100 words, that's truely tiny ... and its so fast!

I wasn't aware watchdog needed to be turned off, but I could see that being a problem I suppose, if the bootloader remained in a loop for an extended period of time and didn't service the watchdog frequently, reset!  I wonder if there are a few nmenonics that you can throw at it, disabling the watchdog via software while in the programming loop, and re-enabling it once finished?

[Najim]

Hi JustDIY,

I think you can t do it... Cause when u enable the whatchdog timer when u program the PIC, u can t disable it by software...

Yes the tiny boot it s fabulous...tiny,fast, and u can save all the serial comunication in a file...

Let s go back to work  

Cheers man.

[justDIY]

ok ... I see now in the datasheet

you program the pic with watchdog disabled, but can enable later in software

WDTCON.0 = SWDTEN bit ... enable watchdog in software, page 259, 18F4520 datasheet

seems to only be an option for the 18F series

so that could be handy, startup with wdt turned off with a fuse, but enable it with software whenever it might be needed, and disable it whenever it might interfere!

[Najim]

Yep that s what I understood...

see ya.

PS: very good forum.