Codeloader bootloader front end

[bfmitch]

Back in May, Kasper published a VB program in the Code Library called Flasher. It was made to work with Loader.c that CCS supplies.

I wasn't real happy with Loader.c since you have to link it to your target program. That means that if the bootload process crashes, you have no way to fix it without breaking out a programmer and putting your PIC in it.

What I wanted was a bootloader that would stay resident in the PIC, that I could modify as needed.

At http://www.thebytefactory.com/dl_codeloader.asp , Gary Smithson has published a bootloader program that he calls Codeloader. (For those who don't know, the Byte Factory is a CCS dealer.) He has versions for the PIC18F and the mid range PICs. The source code is there and free to use as long as you keep his copyright intact. You can go to the web page and get the specifics of how it works, but some of the highlights are:
- It stays resident on the PIC
- You can modify the source code to suit your application
- It can work with Hyperterminal
- You don't have to relocate your code during the build

In other words, it does what I wanted. All I needed now was a front end program so I didn't have to run Hyperterminal during development. (I really dislike using Hyperterminal. Probably irrational.)

This is where Kasper's Flasher program comes in. I've taken the original program, renamed it Pic Flash Loader and made it play nice with the Codeloader bootloader. I did make a couple minor changes to my copy of the Codeloader source, removing some carriage returns and linefeeds. Pic Flash Loader shouldn't care about that. If it does, you can modify it easily. I have only used it for a PIC18F452.

Pic Flash Loader can work with a USB interface or converter that creates vitual comm ports.

One of the neat things about PFL is that, since it can take the name of a hex file as a command line parameter, you can put it right in the menus of the CCS IDE. Just go into the Tools | Debugger Programmer menu and add Pic Flash Loader under the Device Programmer section. The command line will look something like this: d:\projects\picflash\software\picflashloader.exe %H
It doesn't like quotes around the command line. I think it's a VB thing.

I've included more documentation in the VB source file.

You can download Pic Flash Loader from:
http://www.swproducts.biz/Downloads/PFL.zip

You'll have to go to the Byte Factory web site to download the Codeloader source and read his copyright info and instructions.

Both Kasper and I are claiming copyright for the new program. Use it as you like, at your own risk. Please give us credit if you use it.

Burt Mitchell (bfmitch)

[chingB]

Hi,

I downloaded the codeloader program it to my PIC18F chip without modification and I have a hello world sample program which is to be bootloaded later.

I use your VB PIC Flasher with no modification and open the hello world program then press the flash button... with it will send a "=" character until it receives the "wait" and "load".

My problem I encountered is I received a timeout error as reported by the VB program.

to make sure I have my serial com working I decided to make a simple program by using the hyper terminal and send a series of character then after 10seconds it sends the character back to the hyper terminal... it works fine...

with the codeloader... i don't know wat seems to be the cause....

BTW, I am using a PICDEM 2 Plus Board from Microchip.

Anyone encounter this problem?

thnx

[bfmitch]

Since the timeout doesn't start until the "Wait" and "Load" are received, it sounds like your baud rate is OK and you have a good connection.

With Codeloader programmed into the PIC, start Hyperterminal. Hold the '=' key while you turn on the board. If you get the "Wait" and "Load" prompts, use Hyperterminal to send your Hello World program to the PIC. See how that works. Make sure that Hyperterminal is set for Xon-Xoff


Some things to check:
- Go into your com port settings in the Device Manager and set Flow Control to Xon - Xoff. FYI: The MSComm control can't be set to Xon Xoff handshaking or it intercepts the characters and the program won't get them.

- Make sure the FUSE settings make sense for your board.

- I added "Parity=N" to my "#use rs232 settings in the Codeloader source.

[future]

[jtw131]

Anyone know where I can find the app this thread is talking about? The link in the main post is now dead....

[Fabri]

Hi,

I decided to try this bootloader after standard loader.

I downloaded my demo firmware with terminal without problem but PicFlashLoader give me every time a timeout error writing PIC.

I tryed with PIC18 and with PIC16, set to Xon-Xoff, without port buffer, introduced also Parity=N to my "#use rs232" but I have always timeout error.

The only difference is clock of my board , 16Mhz, but I think it'snt a problem for software.

Were's the problem ?

Thanks for help

[Fabri]

Hi,

No body can help me on ?

Regards,
Fabri