Why use a bootloader?

[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"...

[mister_e]

Yup, but MicroCode do more check than Tiny... this is why Microcode firmware is 'round 2.5 time bigger than Tiny.

Sometimes there's a price to pay if you want reliability or speed

[Fredrick]

Yes that´s true.

But with microcode and manual reset i have to program the PIC severel times whit the same program before the PIC starts...

So i think something is wrong.

I will do some more tests and then give you some feedback here.

[Fredrick]

Why do you sometimes have the define
DEFINE BOOTLOADER_USED 1

Tiny bootloader works with and without this define so i wonder what does the define do?

[mister_e]

in fact it has to be

DEFINE LOADER_USED 1

What it does? From memory, It reserved the first 4 code location for the bootloader (1-2 nop and a GOTO to the bootloader code (at the end of the code space))

Why it works with Tiny... can't tell, maybe he correct the .hex file for you... but as it's a small program, you're not experimenting issue just yet.

Keep the DEFINE LOADER_USED 1 at the top.