X68000 information sponging

[kamiboy]

Test it how?

Just plug it in and try to measure the voltages coming from each motherboard connector pin?

Thing is, I do not know the pinout of that connector and the only meter I have is a dirt cheap one I got off of ebay a while back for a fiver, including shipping. Thank you china for your dirt cheap wares.

That being said I am not sure if the meter can handle the loads from the connector, though logically it should have no problem.

In any regard, I prefer to wait until after the caps swap before I test anything. A few days wont make a difference. Besides, cylinder caps tend to leak all over the place so I am pretty confident that they are not at fault. SMD's on the other hand...

[kamiboy]

For the deuce of it I decided today to solder off all of the can type capacitors on the exposed bits of my compact.

While I still could not see any signs of leakage I did notice that unmistakable repugnant smell of burning electrolytic fluid during the operation on the PSU.

Anyone care to share their technique to neutralize or otherwise wash away any such remnants?

I've already given all the parts a round under the old tap. Anything better that can be done? I usually use a toothbrush and some isopropyl alcohol, but not sure how much good that will do.

[Ed Oscuro]

Dish soap? The gentle kind.

[Opethian]

all those caps will have to be replaced. You will probably uncover pad/trace damage when you do so. You might have some luck replacing the PSU with an ITX one.

[kamiboy]

I already have all the caps out. There was no trace of any corrosion. I should have the replacement parts tomorrow, so we'll see how things go.

Internally my compact is in a fantastic shape. Hopefully tomorrow by this time I'll be playing some arcade perfect Ghouls 'N Ghosts.

Only thing that annoys me is that ugly thin white film of filth that is left behind whenever I wash the underside of a PCB with toothbrush and isopropyl alcohol. I suspect it is the result of the component glue being dissolved and spread across by the brushing motion. I really should stop doing that and stick to soap and warm water.

[SuperDeadite]

Hate to burst the bubble, but Daimakaimura is certainly not arcade perfect. It's a wonderful port, but it ain't arcade perfect.

[kamiboy]

Pray suffer my bubble unburst you brute. I have no access to the arcade version so I would never have been the wiser... oh the humanity.

May well, I'll settle for a better port than the Genesis version. The game shall remain as my test game, hopefully I'll get to see it run tonight. Realistically though all those capacitors are going to take me more than a weekday to replace.

[kamiboy]

Well I got around to starting the cap exchange yesterday. Unfortunately, and just as I suspected, there was a lot of leaking and corrosion present once I soldered off the SMD's on the motherboard. And some of the canned capacitors on the motherboard had their legs somehow glued into their holes in a way that made it almost impossible to remove no matter what I tried.

I battled with getting just two legs out of their holes for a few hours, hour!, that was not fun. I would not be surprised if I managed to damage some trace while battling with those two damn legs, what gives? I should have just left them in and soldered the new capacitors on top, but I can stubborn once I get started on something.

I also noticed some chip legs and subsequent traces had been badly corroded by leaky SMD's. Looking at this motherboard I have a feeling these corroded traces will give me a lot of issue once all capactiors have been replaced.

In any regard, I wont know for sure since my capacitor supplier got my order wrong so I am missing some components. Next week it is then.

[kamiboy]

Well lads, it seems the stars aligned allowing for a once in a decade shipping miracle. The capacitors made it to me after a mere day's delay, just in time for the weekend.

But such as it is with all miracles in my life, this one was not half, not even one third, but a mere quarter of assed miracle.

Here are some issues that I hope you X68000 savants can help me with.

First, a minor issue. The PSU fan is really obnoxiously loud. And not by way of a healthy harmonious hum either, it sounds a bit more, how should I put it, metallic to me. Do the Compact models have subpar fans or is this in need of some grease, or replacement?

Before I continue I should mention that currently my Compact motherboard is functioning sans the backup battery as I, upon measuring it to be dead, soldered it out without a suitable replacement. I thought I'd mention that detail before describing the symptoms.

On the bright side my Compact seems to be in well enough repair to start up and display something on the connected monitor. However, it seems that right there is where its tange of utility ends.

Seeing that the two floppy drives are labelled 0 and 1 I assumed one is suppose to use 0 as ones primary disk drive. So I inserted adisk into it and turned on the Compact. The machine starts but after a few seconds it spits out the inserted disk and prints a message which I interpert as "cannot read from disk".

Now for the strange part, if I thrm pull out the disk and put in another disk into the same drive the drive light turns green but nothing happens. The message does not disappear and the disk is not spat out again, the machine does nothing.

Drive 1 acts differently though. If I insert a disk in there the drive light turns red instead of green as it does on the other drive and after a few seconds the disk is spat out with a message about Human.sys.

Now the funny thing is that if I insert another didk into drive 1 the message goes away and the machine seems to try and read the disk but once again spits it out with the same message.

It seems to me like something is wrong with drive 0. But what about drive 1? Can the compact games or human68k from drive 1, or does it have to be drive 0?

I've already replaced every capacitor on the system except one surprise secret one in each floppy which was not mentioned in the NFG capacitor chart. It could be those two capacitors at fault. Or maybe some damaged traces from the great motherboard leak, or the disks themselves.

I doubt it is the disks, the command prompt program I used to write them with verifies them to be correct after each write. Windows cannot read 1.2mb formatted disks right? Because XP does not recognize the disks.

[kamiboy]

Update:

Okay, so it seems one of the floppy drives is no good as I tried swapping them around and changing the jumper and sure enough now drive 0 and 1 have swapped behaviours.

Just for fun here are some shots of the various error messages being spat on screen.

Cheers

[SuperDeadite]

Those messages indicate that they are not compatible disks. Meaning, the floppies are bad. It's possible your drives have issues as well (the Compact drives die a lot more often then the 5.25 from what I've seen). But first, I'd try a real disk, or at least one proven to work on another system.

[Opethian]

what program are you using to write the disks?

[kamiboy]

Real or proven disks are not an option as I have none and cannot get my hands on any in a reasonable timeframe.

On XP I use that generic USB floppy sold everywhere on ebay to write on brand new Verbatim 3.5" 1.44 floppies using ntawrite.

Below is an example command that I actually used to write one of the floppies:

format a: /fs:fat /v: /a:1024 /t:77 /n:8 /y
ntawrite -n -f HUMAN302.XDF -d a

The program writes the image and then verifies it. I once used another program to dump the written image from a floppy and managed to boot the dump using a emulator.

[kamiboy]

Update:

By taking a gander at the insides of the floppy disks I confirmed that one of the drives does not spin the disk upon insertion while the other one does.

So anyone know what could cause the disk not to spin?

Could it be one of the caps on the upper board, or is it that secret cap on the underside?

I suspect the latter, looks like I have some diassembling to do. Bah!

[kamiboy]

Update 2:

Found a suitable temporary replacement for the undocumented cap on the bottom board of the floppy drives and managed to replace them. Now both drives seem to spin but I am still getting the same error messages when trying to load various disks.

At this point either both my floppy drives are toast or there is something amiss with the disks I've written.

Somehow I suspect the former. When I insert a disk it only takes a few seconds before it is rejected. I have a hard time believing the floppy drive has time to actually read the disks in such a short time.

Can anyone tell me how long their Compact takes before rejecting an inserted floppy?

[kamiboy]

Update 3:

After fiddling with the floppy cable and other areas a bit I can sometime manage to get floppy drive zero to try and read a disk.

After a few seconda of reading I get this message:



I think it means that the system could not be started, please reset.

After pushing the off button I get this even more dubious message:



Looks like some sort of bus error?

Anywaste, it looks like this machine has some serious issues. Can anyone offer any input? If not any suggestions as to where I should turn to?

I'd go to NFG but that forum pretty much seems to be dead.

[kamiboy]

ファイナル Update:

Pro tip kids, when trying to boot floppies make sure that little switch on the back of the compact that sets the assignment of the internal floppy drives to 0&1 instead of 2&3.

Once given the correct assignment floppy 0 seems to work more or less well. There are two floppies from which it can read. Floppy 1 does not fare as well. It can read a floppy but when trying to load a game it always fails half way through, so no multi disk game for me.

I was testing a few different 1 disk games when my USB floppy drive decided to stop functioning. Computers, eh gents, dont you love them?

Anywaste, long story short I now have a half functioning compact what cost me hundreds, huzzah!

[kamiboy]

Has been a while gentlemen, but I thought it was time for a postscript on my X68000 adventure.

Lon story short, my floppy drives are still no good, I somehow managed to kill one and the other is only half functioning. These 3.5" drives on the Compact models are as fragile as snow flakes.

Luckily after much trouble I got a internal CF SCSI drive going and finally had time to sit down and play some games.

A pro tip regarding choice of display. The thins came bundled with multisync monitors that could display 31khz, 24khz and 15khz signals. Since 24khz was rarely used and the OS runs in 31khz one would think that pairing thia thing with a multisync PVM would be ideal, right?

Unfortunately that would be a no. The 31khz signal put out by the X68000 is really quirky and exhibits unsightly artefacts when viewed on a PVM.

It is fine for navigating the OS to launch games, but not useful for playing 31khz games. Unfortunately some of the premier titled for the system are 31khz only, like Akumajou Dracula.

If you connect a regular PC monitor to the X68000 then 31khz games look fine. Unfortunately to my eyes games like Akumajou really need scanlines badly. The pixelated 31khz looks like an eyesore and 24khz does not work on PC monitors either.

In my opinion to get the best out of the system it should be paired with a 31khz to 15khz converter and connected to a PVM. Of course I am not sure if the quirky 31khz of the X68000 is down convertable or not.

Since we are on the subject, when will we have a proper affordable 31khz to 15khz solution like the SLG for the opposite?

[SuperDeadite]

Dracula looks fine in 31khz on a real sharp monitor at least. Most likely your displays don't know how to handle the 512x512 resolution properly. Anyway if you want to run everything in 15khz here is all you need:

http://www.cityfujisawa.ne.jp/~fumiki/x ... 8disp.html

Just download the driver there and add it to your config.sys file.

[kamiboy]

Wow, if this thing works then thanks a lot.

Fine is relative though. My display seems to handle Akumajou fine, I just dont like that PC look as far as low resolution fixed pixel sprite work is concerned.

I'll report back once I have that driver on my X68000.

[kamiboy]

It seems that download link had long given up the ghost and not even google can conjure up any alternate copies. So, unless you happen to have a copy handy then that file may very well have gone extinct on the internet.

[Ed Oscuro]

Question regarding MIDI units:

I should have a CM-64 soon. I already have MT-32 units.

Is there any situation where I would still benefit from a CM-32P?

[SuperDeadite]

A CM-64 is a 32L and 32P in one unit. Like if you open up the 64 it's just both mobos shoved in one box with cables attaching them. It's the exact same thing only requires a lot less cable mess to use. The only point of a 32P is too upgrade a 32L/MT-32 to a 64. Well for game use, as a standalone unit the 32P has a cult following in the musician world.

[kamiboy]

About the disp15.x driver. It does not work for games. It does however force the command prompt to run in 480i.

[Ed Oscuro]

Well for game use, as a standalone unit the 32P has a cult following in the musician world.

But they could simply use a CM-64 instead, right?

Basically, will the MIDI commands intended for a 32P only use the 32P capabilities, without triggering the LA synthesis side (and any "unintended") synthesis or otherwise being interfered with by the CM-64 combination? It would seem they should. I still felt I had to ask because there's two "systems" in a CM-64 but just one set of MIDI inputs / outputs (and a passthrough).

[SuperDeadite]

Well for game use, as a standalone unit the 32P has a cult following in the musician world.

But they could simply use a CM-64 instead, right?

Basically, will the MIDI commands intended for a 32P only use the 32P capabilities, without triggering the LA synthesis side (and any "unintended") synthesis or otherwise being interfered with by the CM-64 combination? It would seem they should. I still felt I had to ask because there's two "systems" in a CM-64 but just one set of MIDI inputs / outputs (and a passthrough).

The CM-32L like the MT-32 only uses MIDI channels 2-10. The CM-32P only uses MIDI channels 11-16 (and i believe 14 is locked to the expansion card port). Therefore they have no effect on each other. You'll notice the 32P only has a MIDI input and thru. When linking a 32L or MT32 and the 32P, you send all data into the 32P first, then use it's Thru to the input of the 32L/MT.

[Ed Oscuro]

Thanks for clearing that up. I expected something like that would be the case but just didn't know the details.

I'll probably give the CM-32P a test run anyway but it's probably going into a sales thread now.

[SuperDeadite]

CD-Audio patch for X68000 Space Harrier. It's programed for the Sega Game Music Vol.1 CD. Giving you the real arcade soundtrack in high quality CD audio. Of course you can make your own custom mix too. This was a fan made patch, quite nifty considering Sharp never supported CD-ROM drives for this computer.

http://youtu.be/k53n_gLeXQ4

[ED-057]

since this seems to be a general-purpose X68 thread I'm posting this here

http://www.hyakushiki.net/vgm2x.zip

It can convert a .vgm file into a human68k executable. vgm file must be uncompressed. Genesis and SMS ones should work but PSG emulation is buggy, no noise, also no PCM, no LFO. Sources included.

[kamiboy]

So about the MU80. I know I bought this thing three years ago, but I could only be arsed to hook it up yesterday. Anyway, one of the plus points of the unit is that it has an audio input, so in theory you do not need to toss a mixer into an already rather messy midi X68000 setup.

I say in theory because the mixer functionality is rather badly implemented. It is off by default, so you have turn it on in the OSD. But what really sucks is that every time a new midi track is started by a game, in my case Akumajo, the settings reset and mixing defaults to off. This includes the same track restarting, like say after you die and restart.

Anyone familiar with the MU80 who knows a solution to this?