Upgrading my old I/O board for low lag input devices

Discussion of keyboards, gamepads, joysticks and other input related peripherals.
sk8er000
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Upgrading my old I/O board for low lag input devices

Unread post by sk8er000 »

Hello,

I've bought my mister a while ago and it came with the LLAPI input device from bootsector. It works really but I'd like to try snac too (mainly because of the possibility to use a USB device too).

My questions are:

I've read that for some adapters like the mega drive one I need the last revision due to a lack of connections on older revisions. Is it possible to find a scheme to add those connections to my 5.5 I/O board?

How is possible that my actual LLAPI input device is working with a 6 button controller with my actual I/O board?

Thank you in advance
drgruney
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Re: Upgrading my old I/O board for low lag input devices

Unread post by drgruney »

Sorry this doesn't really address your question, but ... What do you mean by "use a USB device too"?

SNAC uses the user serial port, which is physically a USB 3.0 connector, but it is not a functional USB port.
sk8er000
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Re: Upgrading my old I/O board for low lag input devices

Unread post by sk8er000 »

I'm sorry for the confusion, I meant the adapter for USB controller (serial port to USB):

Image


EDIT:
OK I misread the functionality of SNAC I didn't notice that you need an adapter serial to usb and then add the usb adapter for the controller. I was thinking that using the serial to usb pcb it will allow to plug some usb controllers to the serial port of the mister..

Anyway the question regarding the I/O board mod to use all the required connection remains.
sk8er000
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Re: Upgrading my old I/O board for low lag input devices

Unread post by sk8er000 »

I compared the schemes of the 5.5 and 6.1 versions and I've tried to add IO6 signal and a pull up resistor for every serial signal:

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Now I need a SNAC with the genesis adapter to test if it works.
The pull up resistors solved the flickering inputs with a relatively long USB 3.0 cable using LLOAD input device
drgruney
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Re: Upgrading my old I/O board for low lag input devices

Unread post by drgruney »

One thing to keep in mind. SNAC adapters are moving to the HDMI connector, so SNAC and BLISS can use the same cables.
sk8er000
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Re: Upgrading my old I/O board for low lag input devices

Unread post by sk8er000 »

Finally I got enough components to assemble a USB snac and a couple of adapters (I'm still waiting PCBs for HDMI snac, PCE SNAC, cables, ports and some LLAMA adapters :? ) but I was able to test the mega drive PCB with a 6 buttons controller and I can confirm that the mod is working!

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