antime
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Post by antime on Jan 12, 2015 23:34:10 GMT
yeah, why trust the experts since you're fairly sure. Ignoring the argumentum ab auctoritate, I'm certainly going to trust my own measurements over a claim I've seen repeated over the last thirteen years or so without ever being shown anything to back it up. A couple of years later I picked up an official memory card and my Saturn had issues recognizing it. It fit looser than my old cart did. I grabbed my dad's micrometer and it was slightly thicker, enough to make a difference. Back then I just played US games so the first memory cart had never been removed. Do you remember how thick it was? A difference of around a tenth of a mm would still fit into normal manufacturing tolerances. Also, a thicker PCB would have a tighter fit. The usual claim is that using one of these thicker carts loosens up the connector so that regular carts no longer get a good contact. Another possibility is that the connector oxidizes, and inserting the cartridge a few times simply cleans the pins. If anyone has a broken Saturn they don't need, it might be interesting to remove the cartridge port and cut it open to examine its design closer.
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antime
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Post by antime on Jan 12, 2015 20:52:36 GMT
This cart has a thicker PCB than the official carts and continued use will damage your cart slot. Has anyone actually ever seen a cartridge with a thicker-than-regulation PCB? All cartridges I've ever seen, both licensed and unlicensed, have used the same de-facto standard 1.6 mm thick PCB. Since it's standard, it's cheap, so it wouldn't even make sense for a clone cart manufacturer to use anything else. I'm fairly sure it is just an urban legend, and the simple truth is that the Saturn's cartridge connector is just poorly designed.
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antime
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Post by antime on Jan 3, 2015 21:43:39 GMT
Some games do not work with the 3d controller. That's why it has the analog-digital switch in the middle. If you switch it to digital, it should behave the same way as a normal controller (in theory). Even in digital mode, it uses a different communications protocol than a regular 6-button controller, but the Saturn hardware handles the difference automatically. It's only really an issue for USB converters and homebrew software that try decoding the I/O lines manually.
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antime
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Post by antime on Nov 1, 2014 20:04:41 GMT
No idea. Some 10-12 years ago they were still common around here, but you don't see them very often anymore.
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antime
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Post by antime on Oct 29, 2014 21:54:23 GMT
Don't know about the numbers, but it was released here, with a localized browser. The only other noteworthy thing is the keyboard, which is just a regular PS/2 keyboard with a Finnish layout, made by ICL.
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antime
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Post by antime on Jul 8, 2014 16:05:49 GMT
No, this is something CyberWarriorX had been working on for a while.
You need a cartridge with a custom ROM, because you need to get the custom loader running somehow - the Saturn still won't boot burned CDs directly.
For the technical details, the SH1 will not load anything from a CD, unless a validation function has been called. If the CD looks like a Saturn game, it also has to pass the copy protection check. On the other hand, if it's some other kind of CD (eg. photo CD, video CD, audio CD) then it can be read just fine. What CWX did was change some data on the disc so that the SH1 no longer recognizes it as a Saturn game disc, and then used his custom AR ROM to load and start the game manually.
This is kind of what Rockin'-B did to load homebrew software burned as audio CDs, and I could have sworn I talked with someone about reading data CDs a long time ago.
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antime
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Post by antime on Jun 30, 2014 4:26:29 GMT
If the code is only ever executed directly from the MPEG card ROM, it is accessed via the CD block LSI, which can decrypt it on the fly. On the other hand, if it's executed from the buffer RAM it has to be stored in clear text, which provides a pretty clear attack route.
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antime
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Post by antime on Jun 29, 2014 17:18:11 GMT
I was under the impression that any code present on the MPEG card was to be transferred to main memory and run from there, but I suppose they could have designed some kind of HAL system for different hardware. It is also kind of a gaping security hole.
Regardless, you'd still have to solve the bootstrap problem.
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antime
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Post by antime on Jun 29, 2014 9:59:17 GMT
My guess is that they're emulating the CD block, and that it's done by using the SMPC to issue a CDOFF command to keep the CD block in reset state, and then decoding and handling the accesses themselves. The /CS2 pin is brought out to the cartridge port, and the photos of the prototype show there's some kind of RAM on board (though it could of course just be used for buffering).
Any game that issued the SMPC CDON command would break this scheme, but I'm guessing they number somewhere between few and none.
If you wanted to use the MPEG port you'd have to backdoor the SH1 somehow, as no code from the cards should be executed normally (at least as far as I know).
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antime
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Post by antime on Jun 28, 2014 18:24:42 GMT
Which pin is the one you mention by the way? I see no option to select input, both (CD Block input) and (cart port input) goes into a 74157 multiplexer, and the output of that goes directly into the SCSP AUX pins. The SSEL pin (B3) is connected to the multiplexer's SEL input.
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antime
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Post by antime on Jun 28, 2014 18:13:52 GMT
Transferring saves from the "Sarooo" to/from the Saturn in a boot menu obviously won't be a problem, but if the cartridge is already being used to load CD image data, is it possible to also have it function as a RAM cartridge or memory cartridge during gameplay? Yes. A cartridge can't function as eg. a RAM cart and save cart at the same time, because every cartridge type has an ID, and as far as is known, Sega didn't design a combined RAM+save cartridge so there is no type ID for having both functions simultaneously that games would recognize. Action Replay-type boot menus don't need a type ID and neither would this CD emulator.
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antime
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Post by antime on Jun 28, 2014 15:30:31 GMT
There are still several things I'm not sure how they're handled, but bandwidth and CD audio are not issues. The cartridge port sits on the same bus as the CD block, so data transfer speeds to the main memory should be identical. There is a pin on the cartridge port that selects if the SCSP's external audio input is taken from the CD block or the cartridge port.
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antime
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Post by antime on May 26, 2014 21:57:34 GMT
New burners are not as thorough. the microscopic pits on the disc are less defined today than they used to be. By burning at a slower speed, it gives the laser more time to peice the disc thus resulting in more defined pits. CD burners don't burn holes in the disc. The disc is coated in a dye, and when heated by the laser, its reflectivity changes. Most of my bad burns have in fact been caused by forcing too slow speed. My best guess is that modern dyes are formulated for high writing speeds, and slow writing speeds may cause heat build-up which affects the dye over a larger area than intended.
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antime
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Post by antime on May 10, 2014 23:38:52 GMT
You use whatever program you know how to use. Then you write a tool that converts the data into a format suitable for your engine, and that takes the graphics hardware specifics into account.
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antime
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Post by antime on May 8, 2014 17:34:33 GMT
if you don't mind me asking how hard would you say it'd be to run game code off a cartridge, and to get an EEPROM on a board? The cartridge has 256K flash on it, and is currently used to store the data transfer client which runs directly on startup. So yes, it's possible. It kind of depends on what you need. I believe you'd be limited to 64MB of space, without extra electronics. Cafe-Alpha has been working on putting an SD card interface on a cartridge, but I don't think he's got it working yet.
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