PCEngineFans.com - The PC Engine and TurboGrafx-16 Community Forum

NEC TG-16/TE/TurboDuo => TG/PCE Repair/Mod Discussion => Topic started by: xantoz on August 05, 2017, 05:44:50 AM

Title: MultiTap/TurboTap protocol and/or schematic
Post by: xantoz on August 05, 2017, 05:44:50 AM
Hi, lurker posting for the first time

I currently have a project making myself some wireless controllers for various retro consoles (yes, yet another one of those). Thus far I've gotten a PoC SNES sender (I just use the extant shift register in the controller, so it would be possible to just make a plug-in box to make un-modified controllers "wireless") and receiver working. In addition I intend to use a unified over-the-air protocol making controllers interchangeable between different consoles.

I'm currently looking to implement the receiver side for PCE, and as I would like the ability to support several controllers to one receiver at once (the nRF24L01 I am using natively supports 5 RX pipes, how convenient!), it would be nice to implement a native multitap in firmware at the receiver end. This way I do not need to have 5 plugs coming out of a box into a multitap into the PCE. I am trying to implement as much as possible in firmware, to keep the count of external components low.

However, while I have been able to find documentation and schematics on the PCE pads (including ones with turbo functionality and the 6-button pad) I have found none on the multitap.

If anybody has any clues it would be helpful. Right now my only idea is to hook up a logic analyzer to the multitap and observe it in action.
Title: Re: MultiTap/TurboTap protocol and/or schematic
Post by: thesteve on August 05, 2017, 06:49:35 PM
Hi, lurker posting for the first time

I currently have a project making myself some wireless controllers for various retro consoles (yes, yet another one of those). Thus far I've gotten a PoC SNES sender (I just use the extant shift register in the controller, so it would be possible to just make a plug-in box to make un-modified controllers "wireless") and receiver working. In addition I intend to use a unified over-the-air protocol making controllers interchangeable between different consoles.

I'm currently looking to implement the receiver side for PCE, and as I would like the ability to support several controllers to one receiver at once (the nRF24L01 I am using natively supports 5 RX pipes, how convenient!), it would be nice to implement a native multitap in firmware at the receiver end. This way I do not need to have 5 plugs coming out of a box into a multitap into the PCE. I am trying to implement as much as possible in firmware, to keep the count of external components low.

However, while I have been able to find documentation and schematics on the PCE pads (including ones with turbo functionality and the 6-button pad) I have found none on the multitap.

If anybody has any clues it would be helpful. Right now my only idea is to hook up a logic analyzer to the multitap and observe it in action.
OK I recently actually did this
The pce has 2 outputs and 4 inputs on the port
On 1 controller the line simply enables the controller or swapped but in the tap one causes a counter to select the next controller, and the other resets the count
The counter needs to loop after last controller

Sent from my HTC One_M8 using Tapatalk

Title: Re: MultiTap/TurboTap protocol and/or schematic
Post by: xantoz on August 06, 2017, 08:42:24 AM
So the enable line is held low, and you switch controllers as the select line ticks, resetting as enable goes high? Similar to how the 6-button pad sends DPAD all pressed and III IV V VI every other enable pulse?
Title: Re: MultiTap/TurboTap protocol and/or schematic
Post by: Necromancer on August 07, 2017, 03:10:16 AM
I'm too dumb to help with any tech stuffs, so I'm just here to say welcome aboard and good luck with your project.  I like my wireless PCE pads, but I'd love a modern wireless controller (no line of sight shat).
Title: Re: MultiTap/TurboTap protocol and/or schematic
Post by: thesteve on August 19, 2017, 05:12:30 PM
(http://scontent-sea1-1.xx.fbcdn.net/v/t31.0-8/20989219_10207624584051414_1999850446767350690_o5634.jpg?oh=c4e6d7ff5b4f0d4e6b3c366dab22155a&oe=5A1FBBD5)
Title: Re: MultiTap/TurboTap protocol and/or schematic
Post by: thesteve on August 19, 2017, 05:14:20 PM
thats the 2port, but the 5 should be easy to extrapolate from it
note that those switch chips cant be stacked but i found some that can
Title: Re: MultiTap/TurboTap protocol and/or schematic
Post by: ClodBuster on August 19, 2017, 09:56:34 PM
Schrödinger's switches can't be stacked and can.



By the way, I like this project.
Title: Re: MultiTap/TurboTap protocol and/or schematic
Post by: thesteve on August 22, 2017, 12:30:32 PM
I drew this up when I started my cordless project