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bbraun

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Everything posted by bbraun

  1. bbraun

    Mac 128 error 0488DC

    The logic board should have letters on one side and numbers on another, so you can identify regions of the board by the intersection of the two. The locations I gave below should correspond to this grid system. One non-destructive test you can do for the memory is to just overlay a suspect RAM chip with a known good one. Just be sure to get the correct orientation. Just piggyback the good one on the suspect chip, and see if that makes a difference. It's not quite the same as replacing the chip. If putting the good one on the bad one works, you know the bad one really is bad. If putting the good one on the bad one doesn't work, it doesn't really tell you much. But at least it is non-destructive.
  2. bbraun

    Mac 128 error 0488DC

    The leading 04 indicates it is a memory test failure. It is my understanding that the subsequent digits are a bitmask identifying which chips are bad. Typically you see just one bit set, so would hit something like 048000 for the chip located at G12 on the logic board. If you've got multiple chips bad, each bad chip sets a bit in the error code, so 0488DC would be chips G12, G8, F12, F11, F9, F8, and F7. That's almost half the RAM chips, so I'm going to suspect it's not actually the RAM that's bad, but something else causing the RAM test to report the RAM as bad, like the power power from the analog board or something. So caps might be a good place to start.
  3. FWIW, the ROM of at least one of the keyboards has been dumped, but per my understanding of the forum rules, we can't really talk about that here. MESS emulates both the Mac and Plus keyboard as an 8021 (implementation here) I personally only have the original keyboard, although I'm trying to acquire a Plus version (by like 20x for all the compacts I got a while back). But it could be an interesting project to try to build a new keyboard using the same controller...
  4. bbraun

    3 - Powerbook 100's None work.

    They're tin can radial electrolytics encased in a square plastic shell.
  5. bbraun

    3 - Powerbook 100's None work.

    Here's a picture of my disassembled LCD. The 2x4 row of black things are the radial caps. They seem to be 3.3uF 35V as best I can tell. Thanks for pointing those out, I didn't find them in my previous attempts. There are two radial caps on the center controller board, and that's all I could find. All the replacement radial caps I can find for those are too tall to reinstall the front bezel, so if anyone knows a replacement part for that, I'd appreciate knowing what it is. There's none on the brightness/contrast board or the cabling board.
  6. bbraun

    NuBus and drivers...?

    FWIW, cards can provide drivers via the Declaration ROM, but there is no requirement that they do so. They must have a declaration ROM of some sort (otherwise the card isn't mapped into the processor's address space), but they do not need to provide a driver. Graphic cards almost universally do, otherwise you couldn't really boot with them (there wouldn't be any display output until after booting far enough to load the driver, and then even then only if the driver is properly installed and you're not booting with extensions disabled). Apple ethernet cards do not have drivers in the declaration rom (or system rom for onboard ethernet), you need the drivers in the extensions folder. The Asante cards also do not have drivers, they pretend to be Apple cards and use the Apple drivers. The EtherPortII cards actually do have a driver in ROM, which makes things pretty handy when using that card. SCSI cards virtually all have their own drivers in ROM as well, since that's how they boot. When the slot is selected in PRAM, the system ROM uses the drivers in the declaration ROM to "boot". I put boot in quotes there, since different cards do different things from their drivers, most commonly they pass the boot sequence through to the driver loaded from the selected disk's driver partition. Other types of cards are hit and miss. As for what you "should" do, it seems like lots of people have lots of opinions for you to choose from. I've already gone through the "omg, must fill all slots with coolest stuff!" phase, and after accumulating a box full of neato nubus cards, I found I didn't really use most of them. While being neato, their primary function seemed to be converting electricity into heat. As far as graphics go, the speed difference between low end cards and high end cards is largely lost in the rounding error of the last 20 years of technological advancements. The onboard graphics will do 1152x870@16bit just fine with appropriate vram. If you need higher resolution or more colors, get a card.
  7. bbraun

    3 - Powerbook 100's None work.

    When you recap, I'd appreciate pics and cap sizes, particularly of the LCD. I also have 3 non-working PB100's I'd like to fix. I completely recapped one of the logic boards that chimes, but no display. There must be 60 caps on that thing, it took forever. Didn't help. There's a couple radial caps in the display that I had a difficult time locating replacements for that were short enough to fit back inside the case. Anyway, I haven't been able to revive mine, but will follow this with interest and possibly make another attempt at fixing them.
  8. bbraun

    Serial Port Interrupts

    What will likely matter more than hardware interrupt priority is how the software handles each port differently. Normally, the SCC is configured to generate an interrupt per byte received. This would be an excessive amount of interrupts for localtalk at the speeds it operates at. So, the printer port is expected to be used for localtalk, and when it receives an interrupt indicating a localtalk packet, interrupts are disabled and it polls in the rest of the packet. This means interrupts can be disabled for an extended period of time, and could potentially miss data coming in from the modem port. So the localtalk driver also polls the modem port for data while polling the localtalk packet in, and buffers the modem data so it minimizes the chance of dropping data on the modem port while polling in the localtalk packet. The floppy driver also does this, since floppy accesses are performed with interrupts disabled.
  9. bbraun

    Development on SE/30 and Quadra 650

    There is no "Bare metal programming for macs" book. The information you have is more or less the best publicly available information. Guide to the Macintosh Family Hardware is essentially the SE/30 (and family) version of the 650's developer notes you linked to. Designing Cards and Drivers will help if you want to make an expansion board, write a declaration ROM or similar, but it's not really of that much use when wanting to talk directly to the SE/30 hardware. You can look at the NetBSD and Linux sources, since both run on the machines you're interested in. You can also look at the MESS sources as an SE/30 reference. That and spend hours and hours staring at disassembled ROM and/or System code.
  10. bbraun

    Anyone Have a Dead L2 Adjustable Inductor?

    I believe I have one with a bad (or at least crumbled inner core) L2 from the pile of compacts. I could probably also swap cores on another L2. I might not be able to do much for a week or so, I've got some other responsibilities coming up, but should have a lull in the activities sometime next week or so. If someone else is faster, go for it!
  11. There shouldn't be a software reason it's limited to 1 bank. If you were able to get the other lines and connect them to something, the ROM should find them just fine. The ROM doesn't hard code the sizes, it has a loop that iterates over all banks trying to figure out how big each bank is. So each bank is treated the same, whether it is soldered or socketed.
  12. bbraun

    Macintosh Classic II, FPU / Math Card (Picture)

    I'm really not sure about that. I haven't looked at the ClassicII ROM in particular. There's a good chance it has the EDisk driver, which is what the Classic used to boot (also RAM disk driver, and pcmcia flash card in laptops). That driver looks over some set of addresses (I don't recall how it determines that), for a valid header. So, it might be possible you could put a valid EDisk driver's ROM disk image into ROM there and have it automagically bootable.
  13. bbraun

    Macintosh Classic II, FPU / Math Card (Picture)

    FWIW, the ClassicII dev note has the pinout of the connector. It's pretty much just directly throwing the 68882 on the bus, with the only trick being the 16 bit bus, so doubling up the data lines and using the /DSACK 0 & 1 signals. I've put some labels on those pictures, to illustrate. For the most part, the labeling refers to the 68882 pins, not necessarily the Classic2's connector. For instance, D16 on the Classic2's connector goes to D0 on the 68882, and I've labeled it D0: You can also put a ROM in that socket, up to 3MB worth.
  14. Oh, sorry, the 605 only came with 4MB soldered, so you're stuck with a single uninterleaved bank. The 610 and 650 had the optional configs.
  15. To clarify, I don't think 64MB SIMMs will show up as 64MB. Likely just 32MB, which is why you need the 128MB SIMMs to get 64MB per SIMM slot.
  16. There are 2 RAM banks per SIMM slot, and with the stock ROM, those banks are limited to 32MB each, so 32MB x 4 = 128MB, plus whatever is soldered onboard. You can get this by using 128MB SIMMs in those sockets, you just get half the capacity.
  17. I am not aware of any ROM restrictions in this regard. The banks are dynamically sized. I'm not specifically familiar with the 605, since it is slightly different than the other djmemc controllers, but... There are 2 banks allocated for the soldered on memory. If you have the 605 with 4MB soldered, that's all in one bank. If you have the 605 with 8MB soldered, it's 4MB in each of the two banks, which means the banks are interleaved, resulting in about 10% or so faster memory accesses. So, if you're really trying to get the most out of your 605, make sure both banks are populated with the same memory.
  18. To support larger SIMMs, you need a modified ROM (which is why I commented that it needs the ROM SIMM socket populated), at least for Mac OS. I'm really not sure about A/UX, I haven't tried it with the modified ROM. It is likely that it uses whatever the ROM sets up, I doubt it reconfigures the memory controller. Reconfiguring the memory controller while running from the memory you're reconfiguring gets a bit touchy.
  19. bbraun

    Macintosh Classic II, FPU / Math Card (Picture)

    May as well link the source.
  20. bbraun

    BrickOven™ PizzaBox Hack revisited . . .

    You laugh, but I've had more inquiries on this than most anything else I've done that is mac68k related.
  21. bbraun

    BrickOven™ PizzaBox Hack revisited . . .

    Thanks, I'm traveling for a few days so no progress for a little while. I am working with some netbsd folks to incorporate the change, but what's that 90/90 rule? Going from a neat hack to a supportable change will take some time, but I'm working on it.
  22. I can confirm your results. On my LCIII, C22's negative terminal goes to GND, and the positive terminal goes to the PSU's -5V. And the cap matches the silkscreening, meaning the positive terminal matches the + on the silkscreen.
  23. bbraun

    BrickOven™ PizzaBox Hack revisited . . .

    Since I mentioned the project here, I'll follow up on it here. Using 128MB SIMMs on NetBSD with a stock ROM, stock everything centris 650: Using tmpfs: c650# df -hl Filesystem Size Used Avail %Cap Mounted on /dev/sd0a 3.7G 749M 2.8G 20% / kernfs 1.0K 1.0K 0B 100% /kern ptyfs 1.0K 1.0K 0B 100% /dev/pts procfs 4.0K 4.0K 0B 100% /proc tmpfs 1.3G 400M 936M 29% /mnt load averages: 0.28, 0.96, 0.96; up 0+00:25:12 01:17:12 19 processes: 18 sleeping, 1 on CPU CPU states: 0.7% user, 0.0% nice, 1.0% system, 0.0% interrupt, 98.3% idle Memory: 419M Act, 4608K Exec, 7252K File, 12M Free Swap: 922M Total, 922M Free That's 400MB of tmpfs (RAMdisk in MacOS terms. ), and a total of 456MB physical RAM being used. It's not 520MB because I couldn't touch the first 2 banks (interleaving means if it touches one, it touches both) of RAM SIMMs since the kernel and supporting data exceeds the soldered 8MB of physical RAM. But hey. That's a respectable amount of RAM for these systems.
  24. I can hear it crying out for a rom SIMM socket, a rom SIMM, and two 128mb sticks of ram!
  25. bbraun

    BrickOven™ PizzaBox Hack revisited . . .

    Me too! tecneeq: thanks, I've been cross compiling the kernel and whatnot a bit (that's how I did the kernel hack that I think enables the djmemc bank configuration). I was able to get an hp300 bootloader built that works for my setup and a netbooting hp300. Unfortunately, it's not an exact comparison since the hp I'm using maxes out at 48MB, but at least it's an 040 vs. 040 comparison. The hp300 port seems to be pretty stable under memory pressure and large memory allocations, although unfortunately it's swapped in my case instead of physical on the mac68k machine. I could try reducing the mac's memory down to something comparable and rerun the test to see if it panics. The 650 and 800 with a stock ROM work with up to 32MB per bank, with 2 banks / SIMM slot, and 4 SIMM slots. So that gives 256MB, plus the 8MB onboard for 264MB. To get that, you need 128MB SIMMs and then just lose half the RAM due to the ROM's lame djmemc configuration. Same deal with the 610, you just only have 2 SIMM slots. This is all the same as the 605, it's just the ROM initializes the 605's djmemc correctly, which is all I'm really doing: copying the 605's configuration. As for not worrying about RAM, you're not going to get a faster backing store than RAM. And with 520MB, you can fit quite a bit. Like putting your objdir in RAM, which would make linking as fast as it'll ever get. Plus, it's my thing. Coercing the kernel into reconfiguring the memory controller is waaaay more interesting to me than building packages. If it happens to help, great! The ram is recommended by trag, and is fine with macos and a/ux, and with all my poking at the memory controller from macsbug. So I'm pretty confident in the RAM at this point. This is the system I used to develop/test all the 040 and djmemc ROM mods I've done, which include using huuuuge RAM disks and all kinds of other fun stuff. Now that I've got a diskless hp300, I'm thinking of putting macos & the netbsd booter in ROM for the IIfx and running that diskless too. Being an 030, it'll be slower, but doesn't have the ROM addressing limitations I've encountered on the 040's. Trash80: the 630 can take 128MB SIMMs, they just have to be the special ones. link
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