Cool features

Thanks to people who provided fresh, good dumps, I was able to test few things on Rhea.

First, CD+G playback works now. If the Saturn DAC is as abuse forgiving on all console models as it is on my VA0 there shouldn’t be any issues. And here’s how this stuff looks (the graphics and text comes from the CD being played):

CD+G #1
CD+G #2

Since Rhea is capable of clean subcode output, the bug where the player background would dissapear on non +G discs should not happen either.

Second, I’ve added region auto-patching and it works well. Thus, for Saturn, this will be an option available via INI file (so you can easily force all games to the region of your console). There’s also the idea of adding another solder point to Rhea, which could be connected to the lifted pin of the chip controlling 50/60Hz. This would allow automatic switching. Just an idea for now but I like it.

Third, I’ve run quite a few games already and haven’t had any issues. Which bodes well for the next HW revision. I think I’m going to make a dozen or so 20-pin only models for those interested, the 21-pin version will require proper testing first.

54 thoughts on “Cool features

  1. Awesome!! Count me in for 20 Pin #1 board!!! Just let me know when you want payment.

  2. Amazing work, I’m definitely in for a 20 pin board. Pretty exciting!

  3. Awesome! I’d consider a 20pin board and picking up a new console for it, with Region Free doing an Import Saturn wouldn’t be a huge deal, plus I could get it in White 🙂

  4. only a dozen, there going to me mad dash and fight to get the remaining 11 after me.

  5. By the way, i had some issue with my WordPress account.
    It don’t display the same name on my home computer and my work computer.
    well, to be short, I’m Mockylock or sometime moockyloock.
    Sorry ^^

  6. I have some different Saturn Consoles with broken drives, do you need them for testing?
    And yes, a 20pin Version would be nice 😉

  7. awesome can’t wait

    i’m interested in the 20-pin model as well.

  8. I hope you decide to make more than a dozen 20 pin versions. I would be interested in one too!

  9. Wonderful news! I look forward to placing an order in the near future.

      • sure slim/portable are nice features but atm a 128GB sd card costs the same as a 1TB usb hdd, that’s why I’m asking this 🙂

      • I still don’t understand why would anybody want to buy expensive SD or HDD and keep “full sets” on it. It’s easier and cheaper to keep your games on PC or networked HDD, and just use cheap cards for the games you want to play at the moment.
        Also, given that Saturn main CPUs have no direct access to the drive, a proper menu with image selection might not be possible. Do you want to keep pressing the button 100 times to get to the last folder?

      • I was thinking about that, maybe I’m crazy but what about a menu system that reads from a particular “sector” of the emulated disk. On the hardware side you look for this read request and based on how its made you switch the emulated disk.

        Without knowing how much work that’d be it seems like a unique way to work around the “no direct access to the drive” problem.

      • well it’s not that hard to imagine why someone (me for example) likes to have it all stored in one place: you get a 40-50eur hdd, copy everything and be done with it… then just play without having to copy files over or have different cards.
        But if a menu is not possible then yeah, a hdd won’t be any help at all…. assuming a cd image is 700MB and you get a 32GB sd then you can store 38~40 images on it, the button presses are many 😀

      • You can get at least 50 games on a 32gb sd card (depends on the game, you could easily get over 200 for smaller titles), which is probably more than what most people would even want to play ever.

  10. Awesome – the speed of progress is amazing 🙂
    I would like to ask about the region patching / 50/60hz, will these be an option – so people that already have done Sebs switchless mod could decide not to use these features?

    Like many others I would also buy a 20pin version and then head straight out and buy a 20 pin machine lol!

    For others looking for 20 pin machines it seems you can tell from the serial number (This info taken from zyrobs posts at sega-16)

    CD Drives:
    20pin, VA0-1:
    – JVC ENR-007B EMW10447-003E
    – JVC ENR-007B EMW10447-004E
    – JVC ENR-007D EMW10447-005E
    – JVC ENR-007D EMW10447-006E
    – Hitachi JA00292
    These are all 20pin units. The Hitachi drive is rarely found in Japanese units, most commonly on early Hi-Saturns. They also seem to be exclusive to the SKC-1000 and SKC-1000C.
    There is a small difference in the microcontrollers used between ENR-007B and D.

    A machine with the serial AD51036230 is a VA1. You can tell from the serial:
    AD – manufacturer code
    5 – date, 1995
    1 – board revision number, so VA1
    036230 – # of unit produced

    So the above should be a 20 pin drive 🙂

    • the 50/60 is down to the system so the board would have to have a solder point thats either pulled high or low to set the region, but you could always not solder it if you wanted to use sebs excellent chip?

  11. I really like the auto-patching and auto-50/60Hz feature!

    • Just checked my Saturn and the drive controller is a EMW10447-005E, so looks like it’s a 20pin model – I do remember trying to get a modchip for it years ago and couldn’t as they were only available for the ‘other’ type.

  12. I got a 20-pin drive as well, I’m very interested to get one !

  13. I’d be interested in one, provided the price will be similar (or perhaps less) than GDEmu. I don’t know what model Saturn I have, but mine is in perfect working order. However, I’d source another Saturn specifically to try something like this, because I like the thought of leaving my Saturn discs in their original cases and not risking breaking those brittle long boxes, as well as the possibility of playing my Japanese games on a system w/o having to use the Pro Action Replay 4-in-1 cart.

    • You might still want the 4-in-1 for the 4M RAM upgrade it provides (and that some games need).

  14. im very happy about this. I havent seen any good saturn developments since the 90s.

    But as to not being able to have a menu because of not having direct access to the main cpu through the drive –

    couldnt the rhea have used the cartridge port instead since it was originally designed to run games as well as things like ram carts?

    the action replay boots its program that way.

    anyway, nice work.

    • Ha, if it was that easy, or cheap, to port CD-ROM based games to cartridge port, do you think SEGA (or game pirates) would have bothered with the CD drive in the first place?

  15. nice work!
    I have both 20- and 21-pins version Sega Saturn(Japanese region one).
    I have heard that later 21-pins version has bug for 68000 CPUs and some game(outrun ,space harrier,etc) cannot work with it.
    So if you check 21-pins version with such game, it may not work well though your emulator works well.

    And I have almost all Japanese Saturn Games, if you want to check some game ,I’ll dump and send it to you.

    anyway, I wanna buy either model.

    • I’ve read about that bug. Apparently 68k CPU was integrated into a single chip with the rest of audio subsystem, but the design they used had a few differences in how it executed certain instructions. If the code was using those instructions it would behave differently and the game would freeze.

      It’s a good thing you reminded me about that 🙂

  16. great News! Please, send me email for any 20pin version available. I’d like to order right away ! 🙂

  17. Hi! I’ll go for one 20pin versión for my model 1 saturn!

  18. Excellent stuff, I’ll have one of these when they are available.

    Still enjoying my GDemu 🙂

  19. In theory, could this work for VCD’s, so long as you have your own VideoCD card installed?

  20. I want a 20 pins as well.

    A chronistic difference seem likely. One might think they started making one model and then switched to another, thus making earlier models having 2x pins while newer models having 2y pins.
    A regional difference of the models seems even more likely, is the 20,21 difference interconnected somehow to where it was originally sold?
    Perhaps they used different factories/production lines ending up in the two pin lay outs? If so, this should also be possible to read out in the serial number.

    My ramblings come from the fact that I bought two saturns now, both 21 pins.
    I live in Europe and the first I bought was made for the european market and I got it for about USD20. A whole box with extra controllers and games. Oh the joy! Sadly it has 21 pins.
    I then ordered a japanese model for close to USD150. No more joy. Even less when it turned out to be a 21 pin.
    Should I start looking for an american model?

    • 20-pin variant is present in the earliest models, and it’s not possible to tell from outside as the so-called model 1’s (oval buttons) can come with both 20- and 21-pin drive.
      Just wait for 21-pin Rhea or buy a confirmed 20-pin Saturn. Otherwise it’s a lottery.

      • Thank you for the reply 🙂

        I am trying to pinpoint it here and could need some help with the reasoning. (Any purchases I make based on this reasoning is solely my responsability and not yours or any one else contributing)
        When you say “early model” what do you mean?
        Saturn was in production between 94-98.
        Then the only possible serials should be AD4, AD5, AD6, AD7 and AD8 where the number is the year it was produced.
        If understood it correctly this SHOULD mean:
        AD4, AD5 CAN have a 20 pin (but not always)
        Can we add AD6, AD7 here?
        AD8 NEVER have a 20pin?
        Can we add AD6, AD7 here?

        Another way to go could be the serialnumber.
        Low number = Early model.
        High number = New model.
        Logic dictates there is a certain number where all machines with a higher number is a 21.
        If I understand correctly a number for the opposite (a number where all machines with a smaller number is a 20) does NOT exist. It seems like more data is needed for this.

        I am quite handy with a soldering iron but am limited to install what others have created. Thus i cannot estimate the amount of work involved in making a 21 pin. Is it just changing the interface with new connections and a tiny strip of code or is it making a whole new board? When you write “wait for the 21pin” I wonder what timeframe you have on that. I am an avid Ebayer and can just buy/sell until i find a 20, but if there is a 21board around a corner I just sit and wait.

      • All I can say is you’re looking for the earliest Saturns being made, but if it’s safe to assume whole ’94 production is 20-pin? That I don’t know.

        There are 3 variants of the 21-pin models, 2 of which could probably work with 20-pin Rhea after some modifications (possibly replacing the flat cable with your own custom 21-wire setup). The last one though… will need more work shall we say.

        There is no timeframe I’m afraid other than “I’m working on it” 😛

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