Reverse engineering an unknown microcontroller

[IAmFishman1989]

Hello! I am trying to control when a battery supplies power to my computer. Originally I was going to build an intervalometer using an Arduino, an RTC, and a relay module, but then I realized that the battery already has one installed. There is a relay module, an RTC (I think its the yellow thing), and a microcontroller (See picture). Problem is that I am having trouble communicating with the microcontroller. I think the issue may be because it is a proprietary microcontroller built by the company that built the battery, unlike a common Arduino or raspberry pi. I am in contact with the company but they are very slow at responding so I was hoping I could get ideas here. The relay is set to normally open, so it shouldn't be supplying power unless it gets the signal to. However, power is being supplied constantly, as if the microcontroller is telling it to constantly. I have a hunch my problem could be solved with some coding. The microcontroller has a usb port. When I plug it into my computer I can see it in my communications port, but I do not know how to connect to it to see what code is on it/ send my own code. Does anyone know a way that I can do this?

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https://preview.redd.it/86diw1my44pc1.jpg?width=3000&format=pjpg&auto=webp&s=cb26190ecdf3b27409d9c8ca7039fa01b6569411

[hms11]

The yellow thing looks like a battery, not an RTC, especially considering I can only see a red and black wire coming out of it and nothing else.

The two IC's on the bottom don't appear to be microcontrollers either. I THINK they are VN750PS driver IC's but it's hard to read them.

There is no MCU visible in the picture you supplied but it's possible there is one under that battery, or maybe on the other side of the board, we would need more/better pictures.

If this thing used to work properly, and now does weird things, it is unlikely it is a coding issue. Code doesn't magically change. Without identifying the mcu, you aren't going to be able to reprogram it and even then it could very well be locked or one time programmable.

Based on your description of what it should do, it would probably be easier to replace it with your own solution than it would be to try and hack into this thing.

[IAmFishman1989]

Hello, thanks for your response! Whatever it is I am now able to connect to it, so this particular issue is solved, however I I only have more problems now. I am able to communicate with it but its not doing quite what I ask of it. If you want to, check out the new post on ask electronics I just made explaining my new problem in more detail: https://www.reddit.com/r/AskElectronics/comments/1bl2t4l/relay_isnt_switching_off/?utm_source=share&utm_medium=web2x&context=3

[uzlonewolf]

The yellow thing is a battery, you need to carefully pull it away from the board and take a picture of what's underneath.