Serial Bootloader for pic18f4550

Hello,

Please can anyone provide me the working serial bootloader code for pic18f4550?
plz it's bit urgent..

i already tried the example code provided my Mikroelectronika but the Pc cant detect the PIC....

By serial do you mean USB or UART (or what)?
There are a number that you can get from the Microchip web site and also from other sources via a Google search.
What program do you want to drive it with from the PC side.
Are you expecting to be able to debug through the bootloader (typically very hard but not impossible) or is this just for field upgrades of the firmware?
How much spare space have you got left over from your app?
Especially for a USB bootloader, do you want to share the USB code with your app?
All of these will affect the choices you have.
Susan

If there exists a serial bootloader, I presume that must be a parallel one! A bootloader loads a program into memory from an external storage device; it can optionally run it too!

What are you trying to achieve as I'm not entirely clear on what you are actually asking for.
A bootloader is code that resides in the microcontroller and can be used to re-program the microcontroller itself. Normally it resides in protected memory (or at least memory that is not supposed to be used by anything else) and does not normally execute except to reload the main application firmware out in the field. (If you are in the lab or factory, then you would typically use a programmer directly connected to the board to take complete control of the device , provide debugging facilities if necessary, and higher speed programming.)
Therefore it typically talks to the outside world via a serial connection via a UART or USB interface.
I have not heard of a parallel bootloader but I suppose there is nothing to stop such a beast being written. However I would think it unusual to require 10 or more pins (assuming 8 bits and control lines) that you would need to a parallel bootloader where 2 is all you need for a UART or USB connection.
Susan

Hi,
i want to UART bootloader code for pic18f25k50...
i just want a working code so that later i can program pic18f25k50 using Com Port only ....instead of pickit 3 all the time.....

Try these. It is firmware for the FSUSB demo board with the 18F4550 chip.
It has a USB bootloader.
**broken link removed**
MCHPFSUSB Firmware User's Guide
MCHPFSUSB v1.3 USB Framework
MCHPFSUSB v2.2 USB Framework
Release Notes for MCHPFSUSB v1.3
Release Notes for MCHPFSUSB v1.3 – Microchip Full-Speed USB
Solutions. January 4, 2008. Table of Contents. 1. What's
**broken link removed** Notes for MCHPFSUSB v1.3.htm
MCHPFSUSB Firmware User's Guide
© 2007 Microchip Technology Inc. DS51679A MCHPFSUSB Firmware
User's Guide Page 2. Page 3. MCHPFSUSB FIRMWARE USER'S GUIDE
https://ww1.microchip.com/downloads/en/DeviceDoc/MCHPFSUSB_FW_UG_51679a.pdf
PICDEM FS USB Development Board User's Guide
Chapter 4. “Using the Demo Tool Application – DM163025” refers to the
“MCHPFSUSB Firmware User's Guide” (DS51679), which describes how
https://ww1.microchip.com/downloads/en/DeviceDoc/51526C.pdf

The mikroE example works fine just adjust the baudrate based on your crystal frequency. With 4 MHz Crystal you can't get 115200 baudrate for UART. Try using 9600 or 19200 bps baudrate. I have done that and it works fine.

RAJPUT VIDISHA said:

Hi,
i want to UART bootloader code for pic18f25k50...
i just want a working code so that later i can program pic18f25k50 using Com Port only
....instead of pickit 3 all the time.....

Click to expand...

18F25K50 and 18F4550 in the title ???

MikroE propose a Bootloader with HID serial terminal ...
as the " Ready for PIC board with 18F45K22" bootloader allready loaded inside the PIC .. but link , even made by a USB cable to the PC Computer,
use a hardware interface FTDI (PIC side) , to load the application program Hex , with a serial link (COM virtual) at 115200 bds....
This speed is very low compare to the True USB link with HID bootloader.

So you have to choose witch bootloader to install into your PIC to be compliant with
mikroBootaloader USB HID
or MikroBootloader USB Serial ( with Hardware FTDI interface).

The 1srt time, you will need to use a pickit3 to install the bootloader inside a new PIC.
or buy a mikroE card with bootloader allready included into the PIC

examples:
- Ready for PIC 18F45K22
- Start USB 18F2550
or more rescent noard
- clicker 2 18F87J50 (with bootloader) <- MikroE USB HID bootloader on PC
- click 18F45J53 (with bootloader) <- MikroE USB HID bootloader on PC
only USB link to load the HEX program.
Very quick...


Othe supplier can provide PIC with bootloader inside ...


or detail to install one ...

RAJPUT VIDISHA said:

Hi,
i want to UART bootloader code for pic18f25k50...
i just want a working code so that later i can program pic18f25k50 using Com Port only ....instead of pickit 3 all the time.....

Click to expand...

Fair enough - as others have pointed out there are lots of options out there.
However, be aware of a couple of points in taking this approach:
- most bootloaders you will find will NOT allow you to debug your code. Adding a bootloader should be one of the LAST things you do.
- the PicKit3 will be a lot faster, reliable and will let you debug the app and bootloader as well. It really should be the main programmer you use for the development phase
- keep in mind what code you will need to run in the PC to communicate with the PIC via its UART. It will probably have to read from the HEX version of the code, handle all of the handshaking with the bootloader etc.. Therefore look for bootloader code that either has a suitable PC companion program or has the protocol documented well enough for you to write your own.
(I've used the term PC above; however if you are planning on upgrading the firmware in the field, then you may want some more portable means to deliver the firmware to the PIC. This might be a laptop, but you might also consider the needs of the field engineer and create a small programmer device for them.)
Susan