what exactly is bootloader??

[CCSADDiT]

i have no idea what it is ...

[asmallri]

A bootloader is a piece of software than is programmed, via an external programmer into the MCU. The bootloader is then used to update the software in the MCU without requiring an external hardware programmer. This assumes that the MCU supports the ability to modify its own program memory space.

The bootloader incorporates safeguards to prevent code beng downloaded ito the MCU via the bootloader from overwriting the bootloader. Bootloaders faciliate rapid turn around of code images and enable an MCU to be reprogrammed remotely. For example, I have equipment deployed thousands of kilometers away that I upgrade remotely. This significantly simplifies product support challenges.
_________________
Regards, Andrew

http://www.brushelectronics.com/software
Home of Ethernet, SD card and Encrypted Serial Bootloaders for PICs!!

[arunb]

Hi,

MCU: 16F877
C Version: PCM 3.1619

The boot loader in the examples section gets overwritten whenever I upload a program , how can I prevent this ??

thanks
arunb

[thb]

Hi,

for the 16F877 I use the Picloader from Dontronics (find it with google...). It has some disadvantages (needs lots of ROM, works through a terminal program like Hyperterminal (this can of course also be an advantage as it works with every computer which has Windows 95)) but is easy to use. Note that there is a special version for the CCS compiler so that you needn't change your code to use it.
If you use another bootloader you might have to reserve some space of the program memory by using the #ORG comand.

Thomas

[Guest]

Ic...

is there bootloader for PIC 18Fxxxx series??

[G-Man]

I use "Tiny Bootloader" over at http://www.etc.ugal.ro/cchiculita/software/picbootloader.htm

I find it to be one of the best bootloaders out there. It works with most PICs that have the ability to self-modify the flash memory (including 18FXXXX devices). Check the website for compatibility. One of the best points is it comes in at under 100 program words! (unlike all other bootloaders that take many hundreds if not thousands of program words). One disadvantage however is that it uses its own MS Windows app to download the code to the PIC (no terminal support etc..)

I'm currently working on a 16F88 with 3700 out of the 4000 program words used and it takes less than 3 seconds to completely reprogram it at 115,000 baud in-situ - how about that for speed! My hardware programmer based on the JDM design takes more than 10 seconds to do the same (not to mention how long it takes to pull the PIC out of the breadboard to put it in the programmer).

[asmallri]

[Guest]

i ve tiny bootloader.
i loaded the bootlader hex file to 18f452 i connect it via tiny bootloader program.
but still i dont know how to write code using CCS & tiny bootloader.
which partions of the code i need to change for using them both?