See attached.
I was given one of these novelty "buttons" where each press has a different sound effect/phrase, seems like chosen at random. These are just mass produced single-sided boards with various different themes, so I'd imagine there would be a way to reprogram the chip with different audio.
I've buzzed out the pins, which seem to be:
Unknown ICPin 1 - Battery positive
Pin 2 - Speaker
Pin 3 - D1 (Unpopulated)
Pin 4 - Switch
Pin 5 - Speaker
Pin 6 - Battery negative
Pin 7 - N/C (?)
Pin 8 - D2 (Unpopulated)
D1Pin 1 - To IC Pin 3
Pin 2 - To Battery positive
D2Pin 1 - To IC Pin 8
Pin 2 - To Battery positive
Any ideas where I can start? I do have an EPROM reader/writer, but not sure if the above pinout resembles anything standard?
I had always assumed these were based on OTP/eFuse ROMs and are not reprogrammable.
Ahh bugger!
I've even saw Jingle bells IC, which had 3 pins:
Power
GND
Jingle bells
Well there goes that idea. Maybe I can rip the guts out of this one and replace it with a programmable module.
Replace the speaker with an LED (and maybe a series resistor) and you have a randomly flickering light. It's surprising how many random LEDs (tea lights) play pretty little oriental tunes when you shine them into a phototransistor. [Edit: a lot of the more modern ones produce some nasty white noise sounds].