Bung Game Doctor SF III question

I just found a couple of these in a box of junk - but neither of them has the adapter that connects between the bottom of the unit and the cart slot. Does anyone know if the adapter is just a straight-through PCB or if it has any electronics in in? I remember that some of the early Bung copiers (like the Doctor SF 2) had a PAL and a resistor network on that board...

 

Not sure about SF3 but SF7 is just straight through.
Go onto takayi or whatever the site's called that sells them and get the DSP passthrough connectors

 

The units are generally considered to be built like tanks, or so I've heard. So if you get the adapter or find them, it should still work. Only bad thing with the SF3 is that you must use the Floppy Disk unlike the SF6 and SF7 which have a built in parallel port. Still it's a nice item to have.

 

wasn't there SF7 versions that included SA-1 enhancement Chip support i believe?

 

The strange thing is that these units don't appear to have batteries in them at all - which makes me wonder how the game saving is supposed to work



There is a 32KB SRAM on the board, but the power and ground pins are just connected to the internal 5V supply - so presumably the RAM contents would be lost if the copier power was removed. Maybe you are supposed to back the SRAM up to the floppy disk?

The first thing I need to do is get replacement belts for the drives - the existing ones have disintegrated.

I think there were several companies that promised that "real soon now", but they all seem to have been vaporware.

 

@TriMesh hmm, I see thanks for the reply anyways btw one other thing is it possible to run english patch ips game on these copiers through an original cart somehow?

 

No backup unit or flash cartridge has ever supported SA-1. Anyone that promised it back then was just trying to keep customer interest. The only way it would have been possible back in the 90s would have been by removing an actual SA-1 from a working cartridge and putting it into a copier with all the needed mapping circuitry.

The GDSF3 and up are supposed to maintain SRAM and DRAM while the system is off as long as it is plugged in. This means atleast in theory, it is supposed to allow you to load games into DRAM and they will stay there even if you finish playing and come back in a few days as long as you never unplugged the copier power. In practice my GDSF3 tended to end up with corruption I believe. But the GDSF3 had power issues if I recall, some people modified their to give the floppy drive its own power regulator to sort it out.

Still the GDSF3 is a good performer and can play almost all the same games any other device can as long as you have 32 mbits of DRAM.

 

@MottZilla True they could've but i'd wonder why not :/ instead of lying to people since you've explained how easy it is to install it onto the copier machines? Plus if one copier were to have support 64MBit or was it 96MBit could play every single game ever made from Japan? Btw do you know if they were some sort of chinese catalogue magazine showing off the copier and the games you could play on it? If so don't mind if i can see a scan of it?

 

That was kind of what I thought - the memory section is all wired up so that even if you turn the SFC off it carries on running. I also noticed that on the unit that has the 34-pin floppy drive there were some pads that were clearly intended to be used for FDD power - but they weren't being used, and the wires had instead been soldered to the board right next to the 5V regulator. Since the original position was connected to the +5V line used to power the second 16mbit of DRAM I wonder if they were having problems with noise injected into the memory power rail...

I'm pretty sure that if it was easy they would have done it - back in the day, if you could have advertised the ability to run games like Super Mario RPG it would have been a huge selling point. The first problem I can see is that the ROM in a SA-1 game runs at a substantially higher frequency than a regular SNES cart ROM, and since the copiers emulate ROM using DRAM they have to carry out multiple internal operations for each ROM cycle - this is not a big problem when your maximum bus clock is about 3.5MHz, but gets much harder when it's hitting 10MHz.

They would also have to have provided logic that remapped the RAM from a 8-bit configuration (for normal games) to a 16-bit configuration (for the SA-1 games) and switched all the signals over to the right places. True, this is not really a bit deal if you are building an ASIC for the job, but it would put the pin count up and increase complexity.

Finally, they would have had to pull the actual SA-1 chip from carts - and hope that Nintendo didn't change the design in an significant way since that could put them in the situation where they had to redesign the copier (and possibly even respin the ASIC).

Personally, I never saw a catalog of pirated games - the normal approach for the vendors in HK was that they had a bunch of binders filled with sheets of paper with screenshots and basic information about the game (with the latest hot games as the front) - and you just told them which ones you wanted - and they would write the files to floppy, print out a label and put it on the disk. Later on, when CD drives became more common, you could buy CDs.

 

True hmm could be the case so thats why? couldn't the clock bus speed Mhz been delt with in the copier program's menu in the options or before starting the game if it were possible though? And a simple design of one enhancement chip's design can cause a huge issue with manufacturers at the time? As for the catalogue so it's simply a binder that you chose out of the list & then pay after it finishing up including adding the Roms of your chosing in one disc if you owned a copier with a CD-Rom Drive attachment? was it just only in asain HK language or was it in english also? Nice to know that i would to own one of them to look at back in the day or from time to time Do you happen to know if anyone has the scans or actual binder thing in this site? Thank You for your help!

 

I don't believe DRAM speed would have been a big issue. The bigger issue was cost of SA-1 chips. SA-1 chips would have cost alot of money for them to get. Pirates aren't going to invest that much into a product. Remember that while many special chips came out over the course of the SNES life span, most were only used be a few titles. And you'd be adding alot of cost to the design and production. Now SA-1 did eventually get used by many games. But this also was when the shift to 32bit consoles was beginning and there was less incentive to support these odd ducks. About 8-bit versus 16-bit, the CCL Double Pro Fighter had things sorted out so the same 32M DRAM module supported both SNES and Genesis ROM emulation. So that certainly was doable too.

The real problem is if to get SA-1 chips you need to buy a $50+ game to get it, plus you have to rework your design to have a place to put it, then there is the workload of removing the part without damaging it and installing it... You might be talking $100+ more to the product cost. All to play maybe a handful of games? Another thing that *may* have had a little bit of influence would have been it's more difficult to dump SA-1 ROM images. But they could have done that if they wanted too. But lets see, what SA-1 games would I want to play? Well there is a japanese Parodius game. There's Kirby's Superstar, Kirby's Dreamland 3, Super Mario RPG. Dragon Ball Z might be appealing to some. There are other titles but none that stand out as much as those. I definitely don't think it would have been worth adding support for, other than making sure it could work *through* the copier so you didn't have to remove the copier to play the cartridge.

DSP-1 was the only add-on chip that made sense to support. It was easy to add, alot of games used it. There may even be clone/pirate DSP1 chips too.

 

The GDSFIII "adapter" is straight-through. The GDSFII's SPLD handles rudimentary HiROM support apparently, GDSFIII has it fully integrated.

The Bung DSP "adapter" is probably OK to use most of the time, but it's not something you normally want inserted all of the time--it can conflict with large games inserted into the top connector and probably other DSP/enhanced titles.

The GDSFIII is good, but it only has simple memory mapping like a Pro Fighter/Wild Card so it can't defeat copy protection in games and thus numerous games need cracks. Also the real-time save code ("Super" mode) isn't as good as GDSF6/7. Its 32M DRAM limit prevents you from RTS on a 32M game all together.

Only the very earliest copier DSP support used sacrificed Nintendo chips--they were quickly replaced with off-the-shelf 77C25 since it's not good business to sacrifice expensive retail products. Same goes for CIC and cloned CIC. If SA1 games were commonplace and extremely profitable there's little question it would be cloned and the necessary DRAM multiplexing and data transceivers would be integrated.

 

I definitely agree, if the SA-1 had been in far more games it would have been much more profitable and appealing to add support for it. I guess given the other things they could clone there is no reason the SA-1 couldn't have been cloned for a major operator.

Calpis, did you ever hear anything about the power issues with the GDSF3? And did you ever hear much about how well the DRAM is preserved while the system is off but copier remaining powered?

 

I wasn't suggesting I thought it would have been intractable, but considering that people had to use 70ns DRAM to hit the the 120ns access time specification for the fastROM mode then hitting the < 100ns that the SA-1 needs would have required a significant reduction in the amount of timing slack in the design even if they used the fastest commodity DRAM that was available at the time. This is a headache, especially since I would assume that the process they were using for their ASICs was not that fast.

I'm not at all sure I understand your logic here - you are suggesting that they wouldn't have been prepared to buy carts and pull the chips from them - but that is exactly what they DID do with the original DSP support. And sure, you can switch a block of DRAM between x8 and x16 - all you basically need is a multiplexer - but it all adds complexity and delay and degrades your timing margins.

Thank you, I suspected it was just going to be a blank PCB, but I wanted to check.

The cloned CIC in one of these units has "74LS125" on the package - I've never seen one of those in a 16-pin DIP before :smile-new:

 

By the way, you can get/put the save data to floppy or cartridge, I can't remember what the code is for the cartridge but it should be on the net. The best option with these is replace the floppy with a floppy drive emulator (with a USB or SD card)

 

Yes I am suggesting they wouldn't have been prepared to do that because unlike DSP, SA-1 became available much later in the console's lifespan. Something like 1995 for the first game. DSP was available from virtually the start of the console. SA-1 cartridge I believe were more expensive than standard ones as well. And then there is the limited use of it in popular games. My point is not that they *couldn't* do it, it's that it did not make business sense to do it. The SNES was on it's way out by the time the SA-1 hit the scene. By the end maybe 20 or so titles used the SA-1 out of a massive SNES game library. I already named the titles that most people would have actually been interested in. It certainly would have been different if there were say, 50 SA-1 titles with atleast 15 big name titles.

There are good games that need the extra hardware but it's still a pretty short list. While a copier that supported all of them would have been fantastic I don't think it would ever have made sense when thinking about money.