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NEC TG-16/TE/TurboDuo => TG/PCE Repair/Mod Discussion => Topic started by: seefuu1 on December 26, 2010, 05:03:55 AM

Title: How does the pc engine multi tap/Turbo Tap work
Post by: seefuu1 on December 26, 2010, 05:03:55 AM

Anyone have any info on how these actually work (hardware side)?

Title: Re: How does the pc engine multi tap/Turbo Tap work
Post by: SignOfZeta on December 26, 2010, 05:46:18 AM

I'm sure its just typical serial data transfer. There is an encoder in every controller and one in the tap.

Title: Re: How does the pc engine multi tap/Turbo Tap work
Post by: seefuu1 on December 26, 2010, 07:56:10 AM

Quote from: SignOfZeta on December 26, 2010, 05:46:18 AM

I'm sure its just typical serial data transfer. There is an encoder in every controller and one in the tap.

Yeah ,the multiplexers in the pads (also found in genesis/mega drive pads)and the rapid fire ic those i know about,just the multi tap info seems unavailable to find.

Title: Re: How does the pc engine multi tap/Turbo Tap work
Post by: nodtveidt on December 27, 2010, 11:13:13 AM

As far as I know... it works on timing. Apparently the signals are sent in sequence, and the software uses timing to determine which pad is being read. That's what I can figure out from looking at the hulib code for reading multiple pads.

Title: Re: How does the pc engine multi tap/Turbo Tap work
Post by: Twood1130 on January 02, 2011, 03:19:34 PM

I looked up the main IC inside the turbotap, and found that it is some sort of customizable chip NEC was producing at the time.

It features many different possible functions that a developer could use. Including Multiplexing. Which is the part I assume is used for the turbotap.