Famicom microphone question

[Pokun]

Yes I did that last time I tried at least. I haven tried it in a long time now though.

[Sumez]

This thread made me think... and it's probably a dumb question, but I don't know a lot about hardware and electronic.

But if the Famicom Microphone can play its input over the TV audio, and the Famicom expansion audio works by simply wiring the cartridge pin to the console audio out, does that mean a cartridge could potentially include its own hardware to record microphone audio via that same pin, and get a better quality recording?

[Fiskbit]

Yep; Pokun discussed this earlier in the thread. The microphone audio going to the cart is already mixed with the APU audio, though, so if you want just the microphone, you can't be playing anything using the APU (but can using expansion audio).

[aureus123]

This thread prompted me to put together a simple microphone test. This test records about 1.5 seconds of audio from the microphone to PRG-RAM and can then play it back. The audio is 1-bit and 43,653 Hz, which is as close as you can get to 44.1 kHz with constant cycles (41) per bit. It...sort of works, but I find that it's extremely hard to understand the recording.

Thanks for this. Now I wonder if it is possible to read/write data through mic/speaker of the famicom and an adequate modulation (I’m thinking something similar to C64 tapes).

That is, suppose a ROM with a little kernel that is able to convert mic signal to data and to write it on RAM, e.g. $400-$7FF. On could implement a 1K simple game and distribute it through an audio file, then the user only needs to run the kernel and play that file near the 2nd joystick.

Does my idea has sense or it’s crazy??

[lidnariq]

Not only does it sound doable, but ccovell already did that!
viewtopic.php?f=2&t=9909

[aureus123]

Not only does it sound doable, but ccovell already did that!
viewtopic.php?f=2&t=9909

Great Thanks!!