Corrupted TG-CD memory?

[kid_rondeau]

Has anyone ever had a situation like this?

I started a new Dynastic Hero quest, as I do every year around this time. But for some reason, when I try to make the transition from the first calypso/water area to the first town (the one that's infested with walking mushrooms), the screen goes black, the CD spins, loads, and then does nothing. I've waited five minutes, ten minutes...it makes no difference.

Being a reasonably scientific and logical person, as well as a collector of TG and TG-CD systems, I had the freedom to play around with various system components until I found the guilty party...

TG16: OK
TG-CD: OK
Super System Card 3.0: OK
TG-CD Dock: NG

Of course, the game itself could have been part of the problem, but I only have one copy of DH.

So....the dock was the weak link! I asked myself what about the dock was special in any way, and that's kind of where my already tenuous knowledge of data storage becomes even more deficient. The save files are stored somewhere in the TG-CD dock itself, right? Anyone know where? Is it possible for this to become corrupted? I tried formatting my system several times, but this didn't solve the problem.

I guess it wouldn't be that hard to swap out the mainboard from my "good" dock (which only has composite out) and put it into my wonky dock (which I've modded with S-Video). Has anyone ever tried this?

Any thoughts, input or suggestions are welcome!

[kid_rondeau]

UPDATE:
It isn't just DH that causes this problem...it's any CD game where there's a save option. As soon as the game progresses to a point where you'd normally be able to save, all loading stops. Very strange.

[SignOfZeta]

That's a new one. I'd assume this is a hardware problem that is going to have you either repairing the dock or getting a used one.

The only thing I could think of would be to reformat the save memory.

[BlueBMW]

I've got a spare loose TGCD dock if you need it.

[Twood1130]

What does the Cd Dock use for saving? Is it a battery, or an NVRAM chip?

[SignOfZeta]

Its RAM kept alive by a capacitor.

[kid_rondeau]

Oh! Do we know which cap? Would it be obvious in any way? Large, or otherwise?

[nikdog]

Here it is on the PC-Engine IFU. I would assume it to be similar in the TG dock.

[kid_rondeau]

hmm...no picture/link supplied.

[nikdog]

http://www.geocities.jp/hiropong_7650/pc_engine/ifu_30_06.jpg
http://www.geocities.jp/hiropong_7650/pc_engine/ifu_30_05.jpg

It's having trouble displaying on the forums for some reason. It works occasionally.

[kid_rondeau]

Ok, the links are there...but they just go to some Japanese Yahoo! error page... what does it say?

[Necromancer]

"Sorry, this page is currently unavailable. Please try again later. If you have any questions, after refering to the help, please contact us."

If you cut and paste the text into a new tab, they'll work.

[kid_rondeau]

Whoa! Awesome! Thanks guys!

[Charlie]

Standard supercap.
They dry out the same as any other cap.

You can use a VOM to check the voltages before system usage, immediately after system is turned on, after the system has run a few hours, and finally after the system has been off a few hours.  The changes in voltage will tell you a lot about the condition of the cap.

You can also connect three 1.5V cells in series, and temporarily connect them to the capacitor (observe polarity!).  Then try a Save, turn off the system for a few hours, and see if the saved data is still there.  If the batteries allow a long-term Save with the system off, then you know it's either the cap or it's power circuitry.

 You should also realize that, even in normal operation, a supercap that has not been powered in a long time may take hours, or even days, to re-form and hold a charge once you apply power.  Have you actually left your system powered on for, say, a full day (overnight?) for the capacitor to charge, then left it off for several hours, before concluding the Save isn't working?

Charlie

[kid_rondeau]

Thanks for the info Charlie!

It's tough to explain my problem with the memory. It's not like it can't save files...it can, so long as it's a chip game. The problem is only with CD games that allow you to save/load files at will (like Ys, or Dynastic Hero). Those games start OK, but once you get to a point where you'd normally be able to save the first time, the screen will not load at all.

Maybe that supercap's got something to do with it, and maybe it doesn't. All the same, I think I'll take a look inside my malfunctioning TG-CD for anything obvious in that neighborhood. If not, I might just swap it out for practice. It couldn't make things any worse!