Why use a bootloader?

[Fredrick]

Ok..

Where do i start if i want to use a bootloader?

I have a PCB with a FTDI232BM chip that convert USB <--> RS232 signals and the PIC is a 18F2550, will it work to program via the FTDI chip or do i have to have a real USB connection?

Where can i download a bootloader for the PIC and a PC software to program the PIC?

[mister_e]

If you're using a USB PIC, you may want to use Microchip's Bootloader. (this one use the USB port) OR PICCoder

If you have MicroCode Studio plus, you already have bootloader firmware in... unless you have to purchase MicroCode Loader.(this one use RS-232 port)

Other option, is to find a freeware, I heard good comment on Tiny Bootloader.(also RS-232)

Once you have any bootloader firmware, you need to dump the firmware .HEX file in your PIC first by using your favourite PIC programmer.

Once it's done, you just need to compile your code and use your bootloader utility to update your PIC.

That's it!

EDIT: See difference from one bootloader to another... DEFINE LOADER_USED 1 have to be used.

[Fredrick]

Well that was easy.... Tiny Bootloader worked on the first try....
The loading time with Tiny bootloader is much faster then the PICkit2 programmer..

[mister_e]

hum, interesting to know. Thanks for your feedback.

[Fredrick]

Hmm i have now also try Microcode studio plus loader and that does´t work good..

I have loaded the right HEX file with my PICkit2 programmer and then when i try to "Compile and program" i get the message "Please reset the target microcontroller" and when i do that with the MCLR pin nothings happends... then i klick on the close button in the right corner of the window and now microcode loader starts to program the PIC, but i have to try severel times before the PIC works after the programming from the microloader.

[mister_e]

It will work all the time if you use their schematic as it add a connection to MCLR and you'll not need to do it yourself... hence why I'd modified my EasyPIC 4 board in the past.

[Fredrick]

But it should work to reset it manualy.

And when using microloader the programming time is slow.. my small testprogram takes about 6 secounds whit microloader and with Tiny Bootloader it takes "0.249 sec"...