Feasibility for PS2/NES adapter (power requirements)

[gmoothart]

Hi,
I have never worked with an arduino before, but I have an idea for a little project and I am trying to gauge how feasible it is before getting started.

It turns out that both PS2 keyboards and NES controllers are fairly simple. The idea is to be able to use a PS2 keyboard as an NES controller by connecting the PS2 wires to an Arduino nano or micro, and also wiring an NES extension cord to the same board.

The arduino would be powered by the 5v wire coming from the NES, and would also need to supply power to the keyboard on its 5v wire. Then I need to write code on the arduino that reads scan codes coming from the keyboard, and emulates a shift register so that it looks like a controller to the NES.

In addition to 5v/ground for both the NES cable and PS2 cable, I would need these input/outputs:

Input:
PS2 Clock
PS2 Data
NES Clock
NES Latch

Output:
NES Data

I'm most unsure about the power requirements. Can I safely power the arduino from the NES via the 5v pin and also provide 5v to the keyboard? There is only one 5v pin, so would I just connect both wires to it?

Rough schema:

Any other things that I should be aware of?

TIA,
Gabe

[Railroader]

Regarding NES supplying 5 volt, the datasheets for the NES is needed.
What model would "an Arduino" be? There is a number of different Arduinos, 10 - 15 maybe.

[gmoothart]

Hi Railroader,
For the Arduino: let's say this one:

Arduino Nano Every

For the NES:
There's no official datasheet, this was the most detail I could find:
https://problemkaputt.de/everynes.htm#controllerspinouts

Every reference I can find lists "+5VDC" as the power supplied by the NES to the controller. Is that what you wanted to know? If you need something else, maybe I can test the port with a multimeter.

TIA,
Gabe

[gmoothart]

I found an unsourced assertion that you can only rely on ~17ma from the NES to the controller. I think that's not enough to power both an arduino nano and a ps2 keyboard. I can still do my project, it just requires powering the arduino via usb which is kind of a bummer.