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  2. LaPorta

    Mac Plus (Probably) that Won't Boot

    Try a known good floppy drive in each machine and see. If that one works, I’d assume floppy drive issues. Could be dirt on heads, head misalignment, or even electronic failure (less likely). If no drive is good in a machine, could be logic board issues or cable issues.
  3. dcr

    Mac Plus with 4MB of RAM

    Thanks all! It seems like the best bet would be to buy a Kensington System Saver just to be on the safe side.
  4. dcr

    Mac Plus with 4MB of RAM

    Thanks for that. I wondered why it seemed sluggish to boot but otherwise fine.
  5. I have three (four?) compact Macs that I cannot get to boot from a known-good floppy disk with System 6.0.8 installed. The backs all say Macintosh Plus, but the fronts vary. So, perhaps these were upgraded from 128k or 512k machines to the Plus. To the best I have been able to determine, they all have 800k floppy drives. (A couple months ago, someone here posted an image showing how to distinguish between a 400k and 800k floppy drive and, according to that, these all have 800k drives.) No sad Mac codes or anything else out of the ordinary. They just spit out the floppy like it has no operating system. Is there anything besides a defective floppy drive that would cause them not to boot?
  6. Bolle

    another simasimac

    You actually want to test between the actual CPU and the ROM socket because of the way the traces are run on the board. They go from CPU passing by the ROM, then the FPU and end up at the RAM slots. The point of failure lies between the CPU and ROM SIMM (either from the cap that’s sitting there or the battery if it leaks) If you test between FPU and ROM it is more likely you are not detecting a possible failure. I have been fixing a lot of boards with several issues (simasimac included) and most of them needed a lot of poking around to find the issue. Any resistance in traces should not matter. Most multimeters will cut out at a certain resistance when set to continuity mode. That cutout level should be low enough to not become a problem on those old boards and the switching speed and driving power of those old components.
  7. David Goodson

    Floppy type utility?

    I found DiskDup+ was the best for this. After you put in the first floppy, it’ll show you the type as it reads it and you can hit Abort & it’ll eject that disk & you can put in another. This is a niche use case, i admit.
  8. Dog Cow

    Floppy type utility?

    Probably there isn't a utility that does only that, but there's an existing disk utility which shows that information. Maybe something like Disk First Aid? Or another disk copy utility? There are plenty out there. I'm trying to think back if I can remember one specific application.
  9. Thanks for your input! So using a MkII and serial might not be the best idea after all. So SoftMPU might work better, if it can be used at all on a 66MHz 486... Are there a lot of these? I'm new to DOS in general. The first computer I got to use ran Windows 9x and I never played any DOS games out of DOSBox. Edit: Well, it seems there are quite a few. Welp. I'll have to investigate that!
  10. Whether this is relevant for the Houdini, I recall for the SoundCanvases and their derivatives, the mini DIN pin outs for the PC and Mac cables were different between each other. As said above, Mac one is indeed a standard beige Mac-compatible serial cable. QuickTime 2(.1?) and OMS do a fantastic job of allowing for re-routing an active MIDI device to anything that talks QuickTime. It's up to the capabilities of the Houdini software if Apple allows for something like that, which might be a stretch.
  11. A few notes. There is no guarantee that the serial port emulation from the DOS card to Mac side will work at all, there may be timing issues with MIDI devices. SoftMPU only works with non-protected mode games since it uses the 486's MMU to port trap writes to an emulated MPU-401 and redirect them. Anything protected mode needs modification directly (very few games can be configured to use a MIDI device on a serial COM port).
  12. Additionally, I just remembered while casually browsing for a MIDI Synth that the SC-55 MkII can be used over serial directly, therefore bypassing the MPU-401 interface altogether. The best part is that it uses a Mini DIN 8, so any straight through Apple serial cable can be used with the SoundCanevas without any modification necessary. As @Bunsen pointed out, it should be possible to redirect that serial interface to the PC part without any visible issue, right?
  13. cbmeeks

    68K (no Mac) Designs OK?

    Small update... This weekend was unproductive. I had FOUR large deployments (for my real job) that took up most of my weekend. I did manage to solder the small QFP-64 68SEC000 to a breakout board. This breakout board will next get 64 wire-wrap pins soldered to it so that I can use it. Next after that is free-running it. Someone asked what OS. Well, at first, I *might* try uLinux just to get it running. But my goal is to develop my own OS. But that is a tall order. Either way, I will keep people posted. Thanks.
  14. LaPorta

    Mac Plus with 4MB of RAM

    Another thing: most of the Pina references talk about repairing damage caused by overheating due to use when not in an air conditioned environment. Chances that you have that are far greater these days than when he wrote the books.
  15. So my Performa 600 was in the middle of installing system 7.5.0. I fell asleep and when I awoke in the middle of the night I found it was asking for disk 7 so I inserted it. As a side note I salvaged a floppy eject motor from my IIci and it works beautifully. So, anyways, I noticed the computer froze so I push the power button on the rear but nothing. Nothing when I hit reset. So I pull the power and plug it back in and now it won’t turn on. It’s been perfectly fine before this. I had replaced the PRAM battery but now it’s removed so anything that needs resetting can drain its power.
  16. Necro Post! This MIDI to serial converter for DOS looks promising: http://bjt42.github.io/softmpu/ And a video of it in action: https://www.youtube.com/watch?v=p3qCIe0TmtQ&feature=youtu.be I haven't taken much time to look at how it works but the limitation @NJRoadfan talked about back in 2013 seems (no Midi expert here) to be easily bypassable now don't you think?
  17. CompaqMac

    Mac Plus with 4MB of RAM

    Does anyone have any good pics of internal fans on a Mac Plus? I really want to ad a Noctua fan to one in the future. Id really love to see one with some well done additions. Id actually love to get a somewhst junked up platinum plus case and cut an opening for a fan in the side.
  18. Scott Baret

    Mac Plus with 4MB of RAM

    Having been around these Macs since Larry Pina was writing, I can say that I've used Pluses with 4MB and no fan without a problem. The likely reason Pina writes this is because the Plus (and earlier) had no fan and were prone to overheating when used in, say, a 9-to-5 environment, five days per week. This is what led to so many analog board failures in these computers. Since the upgrader already had the Mac open at the time, it was likely included as a reference for convenience. Why not put the fan in at the same time if one is to be installed? It saves from opening the Mac again and also saves a visit to the dealer or an order from MacWarehouse. If you do use a Plus without a fan, don't use it as your daily driver. The Kensington System Savers are the easiest way to do it. The only real drawback of 4MB RAM has nothing to do with heat. On a Plus, the startup takes forever since the Plus has to test the RAM. (It's also a good way to test how much RAM your Plus has if you buy a new one and the seller wasn't sure of the RAM--or listed it as 1MB since all but the newest Pluses say 1MB on the rear bucket).
  19. CompaqMac

    Mac Plus with 4MB of RAM

    In the Larry Pina Mac Repair Secrets book, he says that many people say it’s not neccessary to add a fan when you upgrade the RAM. He disagrees and says those people are wrong and you absolutely should be adding a fan at the time of RAM installation. This might be where you heard it.
  20. Crutch

    800k drive won’t spin

    Not sure this is the model number but it says: MFD-51W-10 (last digit might be a D) 30002602
  21. waynestewart

    800k drive won’t spin

    What's the model number on the drive case?
  22. reukiodo

    Mac Plus with 4MB of RAM

    I run a Macintosh Classic with 4MB, which is similar to a Plus, but not sure if the Classic already has a fan.
  23. LaPorta

    SE FDHD Restoration

    Small Update: Awaiting my new speaker connector and capacitors from Mouser, they should be here tomorrow. In the meantime, I took to removing the rust from the rear screw-in bar at the back of the logic board. If you look at some of the first pictures from my original conquest post (first photo here), you can see that the bar was literally coated with rust and corrosion. As I have attested to before, the product EvapoRust is incredible. I immersed the bar (after removal) in it for 12 hours, and literally all rust dissolves as can be seen in the first photo. This saves you from doing any manual labor removing the rust. In something this heavily rusted, it also leaves pits in the metal where rust literally ate into the bar, but that is unavoidable. The next step is gently scrubbing the surface with 0000 steel wool (second picture), and then buffing with Black coarse compound with a buffing wheel on a Dremel tool (subsequent pictures). I'm not making it a mirror finish (that's not how it was made), so doing this without sanding works fine. You can see that it looks far better than the originals.
  24. If you really want to get to this level of identifying a performance issue in Leopard with your software, try downloading Xcode 3.1.4 from the download archives at developer.apple.com and look at the OpenGL Profiler (official documentation) that's installed in one of the /Developer/ subdirectories. The getting started section and monitoring GPU use (to determine if an app is using a software fallback) chapters are the most relevant. Oh yes, top is a good choice for high level CPU latency. Just a simple "top -o cpu" in Terminal should help. I agree though that benchmark metrics are not as good as what you can confirm with your own eyeballs, it's a game of optimizing to make a graph go up and to the right removed from context of what that even means. There's always some significant CPU overhead in calling out to an OpenGL driver. Nothing to obsess over.
  25. acerocknroll

    eBay find: upgraded SE

    Haha, yeah pretty lucky find! I'll definitely do a recap as soon as possible (and yes, the sound is very weak). My soldering skills are... ok at best, but I have a friend who's really good. I'll let her take a crack at it once I order the replacement parts. Speaking of which, the top two T15 screws were completely missing... any source for replacements or specs on the size and thread pitch? Thanks again!
  26. reukiodo

    .img files with old Macs

    Have you tried using 10.4's Disk Utility to convert the image and then try to open it on OS9?
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