Can anyone please tell me what sort of communication does this system use with it's 3-pin layout? I'm wondering if it's serial or usb, I hope you can understand the wiring diagram from the picture I tried to make it as clear as possible. Any help would be greatly appreciated!

 

There are many other serial transmission schemes other than RS-232 and USB.
Some schemes require only one signal line plus ground.
You have to provide more information such as where is this module from and what does it do.

 

I wish I could provide something more elaborate, but as you can see this pic has the text on it erased and I know it uses those 3 pins to read from the second chip (memory storage?) because I know this pic is hooked up to a keypad and that secondary small chip and they use the 3 pins to download data from it somehow. Can I reverse engineer it? Is there any possibility? I'm doing this to prove that someone was using it for illegal purposes, I am not the author.

 

If this unit is communicating with some memory device it is most likely to be an SPI interface. But it could also be a I2C interface. But I will stress that this is just me guessing

 

Tell us where this unit is used. Is this from an X-15 fighter jet, nuclear sub, jet-ski?

 

That might be for in circuit serial programming. If the circuit is powered, ICSP only needs 3 pins; VPP,DATA,CLOCK

And yeah please tell us what it is! The wiring is run in grooves that look embedded in metal (a pro device?), but the PCB etching looks like one-off hobby level.

 

Is it from a gasoline station? I've seen somethnig similar installed in gasoline pumps. The mcu sent pwm pulses to the pump screen to present more galosine liters than what was actually fed into the car's tank. Stupid idea to steal money from every one since if they catch you, every one is against you!

 

i reckon someone's been making the pink slime from ghostbusters two.

 

Thank you everyone for the useful and funny replies, this is a system that logs key-presses and the user would be able to download them to a PC through an unknown interface (that's what I was hoping to find out) and yes it is powered by a round cell battery (3V?) so is it possible this would be ICSP communication? How would u download the data?

 

The blue, red and brown wires go directly to a 4x4 keypad layout and other wires are just the power wires that go to the battery. Everything else is there in that chip factor, how could I download the data from it?

 

A key logger then? Wondering if it is legal...

 

Just like in the movie.

All that pink goo made it turn evil!