Reprogramming Embedded MIcrocontroller on watch with arduino ide

Hi guys,
I was wondering if you could point me in the right direction. I have one of those lower cost bluetooth watches and I was wondering if the arduino ide could be used to reprogram it? I
Or do I need another type of software? If I do, will whatever software I use show me the code already on the device? I want to do this because the watch already has bluetooth, and a display in a nice package. If I could rewrite the code, I don't have to build it from scratch. Thanks in advance.
SR

SteveRogers:
If I do, will whatever software I use show me the code already on the device

It is 99.999% impossible to read the code that is already loaded onto a microprocessor.

Unless you know exactly what sort of microprocessor is used in the watch you will not be able to program it.

Many cheap devices use microprocessors that can only be programmed once.

...R

I can find out the manufacturer. If I do, do they have specific software I can use?

SteveRogers:
If I do, will whatever software I use show me the code already on the device? I want to do this because the watch already has bluetooth, and a display in a nice package. If I could rewrite the code, I don't have to build it from scratch. Thanks in advance.

Most important is to check the uC. Is it an atmel AVR or some other type.
The problem with the excisting code is that it is written with a HEX file. You could get it out, for example with AVRdude on AVR uC's, but getting the original code is near to impossible.
BUT: If your lucky your not the only person ever to hack this divice. Check the interweb! Maybe there is even a schematic!

What is the type of watch?

So, what software would I use to program it if it was an atmel AVR? If it was will the software auto recognize the chip?

SteveRogers:
So, what software would I use to program it if it was an atmel AVR? If it was will the software auto recognize the chip?

With an Atmel AVR you could use the arduino IDE, but only if the chip is recognized by arduino. Otherwise the Atmel Studio environment.

About the firmware already on the chip: Consider it lost. The only way i could think of was retrieving the HEX file with AVRdude and get it back to a C/C++ file. But a quick search on our friend Google got me nowhere. People are all saying it is a very lengthy progress and it's faster to rewrite it.

So unless you know something we don't, like a specialized person at the C.I.A., N.S.A. or S.H.I.E.L.D., try to figure out what type of uC is on there and start looking for people who already tried it. Without that knowledge, it's just purely speculating.

You need to know exactly what the CPU is on that watch before even thinking about programming tools.

If you can’t find that out chuck it in the bin. Even if you can it may not be practical or even possible but until you know there is nothing more to say, IMHO of course :slight_smile:


Rob

SteveRogers:
So, what software would I use to program it if it was an atmel AVR? If it was will the software auto recognize the chip?

As @Graynomad says, this is pointless speculation until you have identified the exact CPU that you have.

It's a bit like wondering how to fly a Boeing 737 when ( A ) you don't know whether you have a Boeing, an Airbus or an ATR AND you haven't yet started flying lessons.

...R

I have identified the chip. It is a TI-CC2541 bluetooth SoC. I am on their website trying to figure out what software to download to program it.

SteveRogers:
I have identified the chip. It is a TI-CC2541 bluetooth SoC. I am on their website trying to figure out what software to download to program it.

The software is on there website under "Software"... Just type "TI-CC2541".

Good luck, let us know if it workes.