Why use a bootloader?

[tenaja]

First, bootloaders are faster than a programmer. Second, ICSP takes up more pins (3), and limits the hardware to the pins. A bootloader only takes two serial pins, and if you already have a serial connection, requires no special treatment. Third, if you have the board in an enclosure, it is safer to have a serial connection to the outside world than your mclr pin.

In reality, from a hobbyist standpoint, it doesn't make a big difference. It is convenient, however.

[Jumper]

Because a bootloader will save tons of money when then enduser can correct the major bugs in the software just by using a serial cable and downloading the patch from internet :-)

In true errata Microchip style...

[Ioannis]

Note that a bootloader (normaly) cannot lock your code on the PIC. So for commercial usage this is a minus.

Ioannis

[Jumper]

Any bootloader can program the pic even if code protection is turned on... it is just access to the code area with a programmer that code protection protects from. Not from inside the PIC.

BUT since you download the HEX file from internet it better be a loader with encryption or the code is public anyway :-)

[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.