Robosapein V2 Bot PCB repair wanted

[Crashpro2003]

Originally Posted by Per Hansson

Check the area marked in a blue rectangle, is that trace broken or is it just an optical illusion?

Guess it's an optical illusion caused by more shitty manufacturing and too much flux paste. Thanks for looking that closely though. Cleaned off paste and the illusion is gone.

[JNP-3R]

Without any obvious fault it gets hard to diagnose these. Unfortunately toys are usually short lived things and documentation is just kinda forgotten about and left behind when the companies move on. Your best bet is finding someone who's reverse engineered one, and even vintage ones with a community around them are hard to get info on unless they're really common.

Since we're focused on the main board, the first thing I'd check would be the microcontroller. Thankfully they've marked the pinout for us, so see it it's getting power (should be between the VD1 or VD2 pins and ground) and if you have an oscilloscope you can see if the clock is running by probing the OS1 and OS0 pins. Another thing would be to see if the reset pin (RST, just above P10) is being held low. Could be an issue with the power on reset circuit keeping the thing held in reset indefinitely.

If all that's good and you're still not seeing activity (no changes on the I/O pins, labelled Pxx, check with a logic probe), then the MCU is dead. The issue there is even if we could get a new part, there's no way to get it programmed. If that's the case then you're probably better off replacing the board (donor from a damaged Robosapien?) or installing another microcontroller of your choice and rolling your own code. You may be able to find someone else who replaced the board in one of these and work from there.