X68000 information sponging

[SuperDeadite]

I would like to hear more about the RAM upgrade details on the Compact XVI.

Not much to say really. The official Sharp internal upgrade is a 2mb board with 2 additional slots. Each slot takes a special 2mb ram chip. Meaning fully loaded you can have 6mbs on it, giving you 8mbs internal. It also has a socket for a 68881 Co-processor as well, though that's pretty much useless.

The XSimVI Compact version is a simple board with a Standard RAM Sim socket. You can use up to an 8mb Sim in it, though it only can use 6mbs max (8mb sims are just easier to find).

[papa_november]

The normal and Compact XSIMMVI boards are even the same PCB - just with different connectors populated.

It also needs to be cloned very, VERY badly, because these things are now going in excess of $200 when all they are are a PCB with a bunch of connectors and a couple of TTL chips.

[Ed Oscuro]

It also needs to be cloned very, VERY badly, because these things are now going in excess of $200 when all they are are a PCB with a bunch of connectors and a couple of TTL chips.

Indeed, I was thinking the same thing.

I might still get one of the originals though, but it sounds like I need to look for a 16MHz-capable, high-capacity one for the XVI.

Any manufacturer names besides IO Data for those?

[SuperDeadite]

It also needs to be cloned very, VERY badly, because these things are now going in excess of $200 when all they are are a PCB with a bunch of connectors and a couple of TTL chips.

Indeed, I was thinking the same thing.

I might still get one of the originals though, but it sounds like I need to look for a 16MHz-capable, high-capacity one for the XVI.

Any manufacturer names besides IO Data for those?

Huh? All XSim boards run at full speed just fine... The speed issue is only on I/O slot upgrades. There's a few other unusual RAM upgrade boards floating about. Like the Polyphonic sound board contains RAM sim slots, as do a few others. If you shell out on an XSimX, it's the only upgrade you need for max capacity.

[Ed Oscuro]

Ah, I missed the part where you wrote "Now the XVI and XVI Compact can have up to 8mbs internal before needed an I/O slot board."

By the by, what kind of upgrade is the Xellent30?

[SuperDeadite]

Ah, I missed the part where you wrote "Now the XVI and XVI Compact can have up to 8mbs internal before needed an I/O slot board."

By the by, what kind of upgrade is the Xellent30?

Xellent30 gives you a 68030 MPU and 68882 FPU. Essentially turning your machine into an 030, but it does require a driver to use. Note there are several versions of the Xellent30 for different computer setups. Even the Pro has it's own version.

[Ed Oscuro]

No picture yet, but it's a beauty...

Does anybody recognize the following, especially w/ regards to capacity and full speed potential? Manufacturer would be nice too.

It's a PCB slotted into the leftmost expansion slot of the XVI along the back (I/O slot I think), labeled X68000 DRAM SIMM (and SIMM12 off to the side a little...what does this mean? I thought 10MB was the most you'd put on a single board).

It has two SIMMs slotted in, with a label proclaiming "N.I.E. is aiming at the highest quality." The SIMMs are populated with 8 Hitachi DRAM chips each, and these are hm514100as7 (Korean-made). According to this they are 26-pin and 4M capacity each (I'd take that to mean each DIMM is 4MByte, for 8MB total) but I only see 20 pins on the DRAMs, although there might be some more underneath each chip.

It's possible that there is 2MB more of RAM (beyond the XVI's standard 2MB) squirreled away somewhere I haven't explored yet (i.e. the base).

[SuperDeadite]

A pic would help. But sounds like the board in question goes up to 10mbs. It might be able to hold more for ease of use, but the system itself can only see 12mbs max. Any beyond that is useless. Using DRAM i'd be surprised it if didn't support 16mhz. AFAIK only the very old Sharp brand boards don't.

The XVI has 2mbs on the mobo, and also has internal expansion which takes an additional 6mbs max. So you can have 8mbs before using an I/O slot.

And for the MIDI haters, here's one reason I love messing with this stuff.
Group X, all 3 music options are completely different. Totally unique songs.

Yamaha SY22/TG33
http://www.youtube.com/watch?v=Add1kL696pw

Roland CM-64/32L/MT-32
http://www.youtube.com/watch?v=f2AxcOexa5M

The Internal only music is also unique, but that can easily be heard in an emulator, not gonna bother uploading it.
All are nice, but the Yamaha easily wins imo.

[Ed Oscuro]

Well, there's 2 SIMM slots on this board, each holding a DIMM with 8 chips, and if the datasheet is right, each DIMM is "4M" (4Mbit). 4Mbit * 8 DRAM chips / 8 bits in a byte = 4MByte per SIMM. I have no idea where the "SIMM12" could come from in this case, unless it is part of a kit that maxes the RAM (but as stated that would have to be in conjunction with another RAM upgrade elsewhere in the machine).

I thought I saw 300ns on one of the datasheet pages (seems slow; that's much slower than the typical 60-70ns Fast Page or EDO DRAMs, but this is a 68000 and not a Pentium...so perhaps that's about right for the capacities listed). Pic coming up in a bit.

[SuperDeadite]

Then could just be an 8mb board as well. It could also have 2mbs soldered directly onto the board itself and the SIMM slots for expansion.

[Ed Oscuro]

From a distance I thought that might be right...but there's no DRAMs on the board aside from those on the SIMMs. For posterity before the photos:

(RM3) 7 resistors?
(U11) TI SN74LS04N (Hex Inverter)
(U9) Thailand S 74F08N 2129L04 9249VE (independent two-input AND gates, four count)
(U6) TI J306X2 SN74ALS15N
(U7) TI SN74LS138N (3-line to 8?-line decoder - hard to read the datasheet)
(U8) TI SN74AS21N (Dual 4-Input Positive-AND Gate) http://www.mouser.com/ds/2/405/sdas085b-102720.pdf
(U10) TI SN74LS31N (Delay element) http://www.mouser.com/ds/2/405/sdls157-193190.pdf
(U3) TI J705C SN74S158N (serves as a multiplexer I believe; "Quadruple 2-line to 1-line data selectors/multiplexers") http://pdf1.alldatasheet.com/datasheet- ... S158N.html
(U4) TI J705C SN74S158N
(U1) TI SN74ALS245AN (octal bus transceivers with 3-state outputs) http://www.mouser.com/ds/2/405/sdas272a-103380.pdf
(RM2) some kind of package I can't read just yet
(U2) TI SN74ALS245AN
(RM1) same as (RM2)
(U12) TI SN74LS32N (quadruple 2-input positive-OR gate) http://www.mouser.com/ds/2/405/sdls100-196241.pdf
(RM4) 7 resistors?
(U5) Hitachi HD74S158P (probably a quadruple 2-line to 1-line data selector/multiplexer)

There are some other small components (resistors, caps?) not listed here, and a two-position jumper switch

Ahh, the good ol' 7400 series...and the Hitachi thing, whatever it is from the 74 series, is still being made. All parts can be sourced really cheap. More of these are begging to be made! Too bad it's not 10MB but whatever.

[SuperDeadite]

Once again a damn pic of the board itself would be a lot more useful.

Anyway just because the sockets are populated with 4mb simms, doesn't mean that's the most it can take. You might be able to replace them with 6mb or possibly even 8mb simms. The XSimVI for example is designed to accept an 8mb simm, but can only use 6mbs from it.

[Ed Oscuro]

Click and zoom on Imageshack to make legible:

Anyway just because the sockets are populated with 4mb simms, doesn't mean that's the most it can take. You might be able to replace them with 6mb or possibly even 8mb simms.

Yeah, I had the same thought about 6MB SIMMs...8MB seems more likely.

[Opethian]

XPC4 works great. I have to see how the downscan works but I think this is the way to go.

[Ed Oscuro]

By the way, there's enough RAM on that card to hold the 6MB of pictures I took.

I suspect the jumper switch selects between using one or both modules.

[SuperDeadite]

That should take 6mb simms for sure. The switch is weird, but I'm guessing that's the replacement for dip switches that all RAM boards have. As RAM needs to be setup as one continuous block, you have to assign them in order.

[kamiboy]

Ah, the lawless days of each computer variation requiring specialized this or that to enable this or that function shall not be missed.

Realizing what a glorious mess the Compact IV memory expansion situation is at has convinced me to stick to the included 2MB and call it a day.

Luckily it seems all the titles that interest me demand no more.

[ED-057]

4Mbit * 8 DRAM chips / 8 bits in a byte = 4MByte per SIMM

That sounds right, and the 7 at the end of the part number suggests 70ns.

I suspect the jumper switch selects between using one or both modules.

One module is only 8-bits wide and the 68K has a 16-bit data bus. It probably won't work at all unless both SIMMs are installed.

6mb simms

No such thing... but I've heard that 16MB 30-pin SIMMs exist (never seen one)

[Ed Oscuro]

Hey, thanks for that. I also thought 6MB SIMMs sounded odd, but perhaps 8MB will work. Maybe the jumper switch selects the selected I/O slot (there are two, after all, and it's a two-position switch)? Other ideas I've had don't seem likely.

Now, a question probably aimed mostly at SuperDeadite:

The Roland M-GS64 has this in its User Manual (on page 17), under the Initialize section:

CM: The M-GS64 can be set to the same arrangement of sounds as the Roland CM-64 (multitimbral sound module). Perform this initialization when you wish to play back song data that was created on the CM-64.

Will this be of any use for X68000 gaming? I see nothing indicating the M-GS64 is capable of LA synthesis; it's a GM sound module. I have some hope because they mention the CM-64 specifically, instead of (for example) the CM-32P.

[SuperDeadite]

It sounds like the standard remap that all Roland Sound Canvas, and all Yamaha's (TG-100 and after) have.

As for 6mb SIMMs. The XSimmVI has different dipswitch settings depending on if you use a 6mb or 8mb simm. I find it hard to believe they went out of there way to have a dip switch setting for a type of simm that doesn't exist...

[Ed Oscuro]

The XSimmVI has just one SIMM adapter, right?

I should dig around the ol' parts box to see if I have any FP RAM. Don't know if EDO RAM would work, but it might.

6MB SIMMs might be out there but they are next to impossible to find (assuming they exist; they'd have to have some strange population of DRAM chips, like 12 4Mbit, or 6 8Mbit chips); hopefully two 8MB SIMMs will work just as well.

Sounds like I'll stay away from the M-GS64 then.

[NWrain]

XPC4 works great. I have to see how the downscan works but I think this is the way to go.

What is the XPC4? Does it have any linedoubling or scaling capabilities? Is it just a vga to dvi converter?

[Fudoh]

Upscaler with 15, 24 and 31khz input support. No scanlines though.

[robivy64]

That video isn't the most accurate I must say.

What was inaccurate about it?

Did I point to the wrong chip and call it the CPU?

I'd love to hear more about how you rebuilt the NFG V3 HDD image I have from scratch. I only see the SX Window partition and "games4" folder directory.

[Ed Oscuro]

Before the popcorn starts poppin' and I forget what I was doing, I wanted to state that the DIP switches on the XSIMMVI I saw are four bits (so 16 combinations) whereas this one has only two. It probably has a totally different function than the one on the board I posted.

[SuperDeadite]

Well let's see, you load up Mahou via LHES. Doing so the game will crash after the ship selection screen. Other games that "don't work" by the way have a similar problem. These games must be run from the prompt only.

As for rebuilding the image from scratch, this is exactly what I did. The original image is a measly 777mbs. And you can't just magically make it bigger. You have to do a totally fresh format. I formatted a brand new 2gb image and setup partitions. Meaning I had a blank image with nothing in it. I had to add in every single game. Doing this via Disk Explorer will give you corrupt files more often then not. Also the original image was based completely off of yucky internet dumps. The old image doesn't even have the full version of Souhou Blue Phoenix, only the stage 1 demo lol. So I went through and used original floppy disks when possible to ensure 100% perfection. Do you have any idea how long it takes to install 2gb's worth of games off floppy disks and test them? Over a month lol.

[kamiboy]

Brief update lads. Even though I bought that compact months ago it actually got into to my hands first time this week.

I hooked it up and no dice. Looks like DOA, pushing the power button did nothing, nothing lit up not even leds. I was half expecting it to be anyway, even though the seller had mentioned it to be working but potentially having some floppy read problem.

Anyway, I very foolishly then started to rip it apart. A word of caution to any repair hopefuls, these things are a pain in the ass to deassemble. I ended up breaking a plastic tab, but it is prolly not a big deal.

But what was most foolish about my hasty taking apart was that I did not document where each piece came off of. I imagine that is going to provide me with a challenge when time comes to put it back together.

Anywaste, I saw no evidence of capacitor leakage, which is good. But with SMD's you never know. Sometimes you find out about the mess of corrosion once you solder one off.

In any regard I have purchased replacement high quality caps for an obscene sum and will prolly get around to do the operation some time next week.

Fingers crossed that it will do the trick.

In other news, the compact is a lot smaller than I imagined. Maybe I could have gone with a regular model after all. Also the plastic around the keyboard cable is crumbling to pieces, I've never seen that before.

[Opethian]

start with the power supply I bet that thing is full of caps that pissed all over everything in there.

[kamiboy]

No, surprisingly the PSU looks minty. In fact all caps look minty. No leaks or swellings to be seen anywhere. Kind of surprised that I was getting no power actually, I was expecting a mess when I opened up the unit, especially in the PSU housing. I'll report back once I got the caps replaced.

In regards to the keyboard cord plastic crumbling, anyone else experience that?

The keyboard is also missing the top leftmost key, anyone know of any viable replacements. I already tried some vintage keyboards but no dice, the keys wont fit.

[robivy64]

Can't really tell how bad leaking is until you pull the caps.

Might as well test the PSU, at the very least.