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NEC TG-16/TE/TurboDuo => TG/PCE Repair/Mod Discussion => Topic started by: ddoubledee on April 23, 2015, 11:44:17 AM

Title: Strange problem with a TurboGrafx-16 when used with the CD-dock + CDROM2
Post by: ddoubledee on April 23, 2015, 11:44:17 AM: As the title says, I have a TurboGrafx-16 system with a strange problem. It seems to play HuCard games fine, but when I try to use it with the TurboGrafx-CD attachment... I notice two strange things...

#1. On the BIOS screen (using an arcade card with a kisado adapter)... where it should say Super CD-ROM2 System... The word 'Super' is missing...

#2. When you press the RUN button, the CD drive doesn't spin. Infact, the CD drive doesn't even power on... The system just hangs at "Just a moment..."

If I swap out the TurboGrafx-16 console with another one... Everything works great! The word SUPER appears on the BIOS screen, and when you press RUN... the CD-ROM drive powers on and displays 'PC'... and the game loads!

What could be wrong with this TurboGrafx-16 system?
Title: Re: Strange problem with a TurboGrafx-16 when used with the CD-dock + CDROM2
Post by: Keith Courage on April 23, 2015, 02:00:33 PM: well, first thing you should do is try cleaning out the card slot by putting some rubbing alcohol on some of the pins of one of the games you have.

if that doesn't fix the problem then Unfortunately there's some bad traces, or a bad chip on your motherboard.

also, double check that none of the pins in the expansion port are bent.
Title: Re: Strange problem with a TurboGrafx-16 when used with the CD-dock + CDROM2
Post by: ddoubledee on April 23, 2015, 05:01:56 PM: Thanks for answering, Keith. All suggestions are appreciated. :) I had the same thought-- perhaps some sort of connection issue in the card slot or in the expansion port... So I did give it a good cleaning. The expansion port pins look good, and they feel like they make a tight connection in the dock.

It's a strange one, eh? I just got the right bit to open the system up and have a look inside. I'm desoldering the shielding right now.

If I can just get this TG-16 to play nicely... I'll have two complete TG-CD machines. Muwhahaha :)
Title: Re: Strange problem with a TurboGrafx-16 when used with the CD-dock + CDROM2
Post by: Keith Courage on April 23, 2015, 07:01:12 PM: Also, have you already tried the back the CD card out of the Hu card slot slightly trick? Don't want to forgot the easy stuff to try first.
Title: Re: Strange problem with a TurboGrafx-16 when used with the CD-dock + CDROM2
Post by: ddoubledee on April 24, 2015, 05:28:14 AM: I tried your suggestion of leaving the HuCard just a little bit out of the slot. Doesn't seem to make a difference. But, thanks. :)
Title: Re: Strange problem with a TurboGrafx-16 when used with the CD-dock + CDROM2
Post by: ddoubledee on April 26, 2015, 05:30:22 AM: (http://i.imgur.com/obnMOHm.jpg) (http://imgur.com/obnMOHm)

(http://i.imgur.com/qqRirHA.jpg) (http://imgur.com/qqRirHA)

I don't think this system has been opened before... I don't see any obvious tampering... But what I do see is some corrosion on the right side of the system... So, perhaps something has been spilled into the system...

I guess, for a start, I'm going to scrub the whole board with alcohol... Then maybe I'll try re-tinning some of the solder joints...
Title: Re: Strange problem with a TurboGrafx-16 when used with the CD-dock + CDROM2
Post by: esteban on April 26, 2015, 07:30:21 AM: That looks like a lassi, or some other yogurt-based beverage, found its way into the the TG-16.
Title: Re: Strange problem with a TurboGrafx-16 when used with the CD-dock + CDROM2
Post by: wilykat on April 26, 2015, 11:29:56 AM: That would affect controller function but it does not appear it would be causing problem with CD system.
Title: Re: Strange problem with a TurboGrafx-16 when used with the CD-dock + CDROM2
Post by: ddoubledee on April 26, 2015, 05:03:30 PM: Re-flowed solder joints on all the chips, the card slot, and the expansion port... No change (Not that I expected this to work... but it was worth a try ;) )

EDIT: I agree, wilykat. The controller port is the only thing on that side of the board. Very strange.
Title: Re: Strange problem with a TurboGrafx-16 when used with the CD-dock + CDROM2
Post by: thesteve on April 26, 2015, 06:38:25 PM: you could be missing an upper address or IRQ2 on the card slot (solder, trace or CPU)
Title: Re: Strange problem with a TurboGrafx-16 when used with the CD-dock + CDROM2
Post by: ddoubledee on April 28, 2015, 08:29:59 AM: Thanks for your help, everyone-- thesteve, Keith Courage, wilykat, esteban... But I'm throwing in the towel with this one. I suspect there is a bad IC. I've got another TG-16 coming to use with this CD system.
Title: Re: Strange problem with a TurboGrafx-16 when used with the CD-dock + CDROM2
Post by: thesteve on April 28, 2015, 08:32:47 AM: parts board
Title: Re: Strange problem with a TurboGrafx-16 when used with the CD-dock + CDROM2
Post by: ddoubledee on April 28, 2015, 08:42:42 AM: You got it :3
Title: Re: Strange problem with a TurboGrafx-16 when used with the CD-dock + CDROM2
Post by: thesteve on April 28, 2015, 09:04:50 AM: if its a chip issue its HuC6280 or work ram
Title: Re: Strange problem with a TurboGrafx-16 when used with the CD-dock + CDROM2
Post by: ddoubledee on May 05, 2015, 07:06:07 PM: I received the replacement TG-16 today, and all is well. It works flawlessly with the CD-ROM2 attachment. Very happy. :)