Modifying a spare original II controller for AV Famicom

[NintendoKing]

I was wondering has anyone managed to do this?

I am wanting to bring the microphone capability to my AV Famicom; as it was my favorite thing to mess with on the original Famicom.

Does anyone have any idea where I would have to splice wires, from the NES controller port part so I can plug the controller in and maintain the Microphone Ability?


This would make my AV Famicom complete, it just hasn't felt quite right without me being able to goof off and talk out of my TV's speakers. 

And finally would said controller also work on my NES-101 Toploader?

[b1aCkDeA7h]

Ahh, an age old question that I too would love to know. My thoughts would be that since the only real difference between controller I and controller II are the mic and lack of start and select buttons, then some of the extra pins on controller II would be responsible for the mic.

However, I'm not good at innovative electronics reverse engineering, I'm only somewhat good at doing the job once the DIY is out.

[Xious]

http://nocash.emubase.de/everynes.htm
http://nocash.emubase.de/everynes.htm#controllersmicrophone

I forgot that the mic was $4016.D2; I had thought it was $4017.D2, which would be an easy hack.
It's certainly still possible, but not as easy as I had thought earlier.

I can try wiring it up to D2 on the 2A03 just for grins to test a theory, I don't know how it'll turn out...yet.

Right now I'm under a lot of stress though, which is messing with my mind, concentration, and general state of being, so I promise no timeframe. I have a lot of projects to complete and a tonne of systems and games to prep for sale for the upcoming holiday season.

-Xious

[NintendoKing]

"On older Famicoms, the second control pad (that without Start and Select buttons) has a microphone with volume control built-in. The signal goes to Bit 2 of Port 4016h (simple 1bit input, not an analogue ADC-converted input).
The signal is also merged with the PPUs sound output signals, as such, allowing to use the television set/speaker as amplifier/megaphone."On older Famicoms, the second control pad (that without Start and Select buttons) has a microphone with volume control built-in. The signal goes to Bit 2 of Port 4016h (simple 1bit input, not an analogue ADC-converted input).
The signal is also merged with the PPUs sound output signals, as such, allowing to use the television set/speaker as amplifier/megaphone."

Interesting, also think you for volunteering to attempt this first, also it's fine that you might take awhile... No rush.

[Xious]

Yes, i plan to try it. My first obvious curiosity is to see what happens if I simply bridge the signal to D2 before the APU and see what happens. If that doesn't work, I'd have to find a way to generate the signal in such a way that the software can see it at the correct register, but I am not certain if it matters, so long as it is on the correct data line.

Until I know that with absolute certainty, I can't say more. I'm sure that I'll get some mouthing from a few people for even considering this, but I'm still tinkering with how software accesses external devices and how it recognizes specific registers on a shared data line...

This is what the mic input looks like: http://atariusa.com/Famicom_Schematics/FC%20Ports%20Schematic.png

It looks interesting, to say the least, and could be reimplemented in the New Type FC with a bit of effort...

[NintendoKing]

It will be a trial and error thing; if you figure it out I would love to get instructions on how to build mine.

[Xious]

Here is my schematic for the Famicom microphone.

I am not yet sure if this is fully correct and/or accurate, but I think it is at least passable. If anybody wishes to verify or correct it, please feel free to do so; let me know if you find any problems, and if you do, please specify what they are and the requisite corrections

This schematic is freely distributable.