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techknight

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Everything posted by techknight

  1. Dont think they exist, most of the time the monitors were engineered by other people and Apple rebranded them. So if you could figure out what they were "originally" you may have a better chance. However, your gonna need to do some troubleshooting regardless.
  2. Remove the SY6522 and see if your consumption goes down.
  3. techknight

    Lubricating hard drive?

    Not without removing the platters. If theres more than 1 platter, you need a special tool. And a clean environment.
  4. techknight

    Sad Mac Error Code 0000000E 0000FFFF

    E codes are caused by bad bus control traces from the CPU. Check the schematics, and check the R/W line from the CPU, that was the cause in the portable anyways.
  5. No, you need an adjustable regulated bench power supply that can feed in 5V with a specified current into the rail. Youll make it worse by experimenting otherwise... Anyways, You already tried ATX power supplies so it kinda renders things moot. You need to power the machine up with a KNOWN GOOD power supply, monitor the rails correctly, and then attempt to find out whats shorted by whats heating up. Something is shedding off alot of current based on your numbers that you provided, and thats the easiest way to find out what...
  6. Or the power supply is weak and is unable to maintain regulation on the 5V circuit. if you had an adjustable bench power supply, you could feed in 5V to substitute that particular rail, and see if the rest of the power supply voltages come up, or if its still being dragged down. If its dragged down, then you need to feel around to see whats getting so hot you cant touch it, as thats the likely issue. But, if all the rails stabilize, and the machine comes to life, its your power supply. Edit: Just saw at the end of your post, you substituted the power. Well, if the voltage is getting dragged down, you either need an infrared flir, or, feel around to see whats getting hot. Something is getting VERY hot. If I am going to hazard a guess, it could be a multi-layer ceramic, or a tantalum capacitor shorted.
  7. techknight

    SCSI2SD Issues

    Yea, Lido is awesome. I use it for everything. I have 2, maybe 3 of these things and I have not had an issue yet setting any of them up.
  8. techknight

    SCSI2SD Issues

    Termination is REQUIRED on a SCSI bus. Period. At the end of the chain. So if there is a SCSI HDD in a Mac, you must terminate this drive. If you plug a drive externally, you MUST terminate that drive too! But if you insert a drive in the middle of the chain, you do NOT need to terminate those drives. only the END OF THE CHAIN needs terminated. If there is only one drive in the chain, That is your termination point. Terminators are there to impedance match the "transmission lines" to prevent reflections, or bus errors.
  9. techknight

    Questions about the SCSI2SD (Macintosh SE/30)

    I think these cards run of the termination power provided by the machine. the Plus doesnt have it, but the SE/30 should so the 25 pin cable is all you need. To get termination power on a plus, you have to install the diode on the logic board that provides it.
  10. techknight

    LC/LCII/CC 68030 accelerator cloning

    Similar logic, but yes. Why reinvent logic equations that already work? Btw if you do that adapter, you will need to power the card externally as the internal power regulator won't hold it... This makes the design tricky, one of the main reasons I want to eliminate the pals. Power consumption...
  11. techknight

    LC/LCII/CC 68030 accelerator cloning

    I remember that thread, I commented in it awhile back. Anyways. I dont want to use GAL/PALs in my design, id rather use the XC9572, something more tightly integrated.
  12. techknight

    HD Access LED Size for NEWER Quantum ProDrive LPS?

    You have 3 main sizes. 3MM, 5MM, and 10MM. I think there was even 2MM LEDs, but eh. I know on the metal HDD plate that goes on the SE and SE/30, its 5MM.
  13. techknight

    LC/LCII/CC 68030 accelerator cloning

    I need this, but for the 68000. Would like to shoehorn an accelerator into the Portable one of these years.
  14. techknight

    schematics - schematics - schematics

    Charles/Uniserver posted them over on Archive.org But only the ones that he was able to get from BOMARC. The guy retired.
  15. Its worth hanging onto any memory upgrades, whether they work or not because they are getting more rare. Its not too difficult with some SMD rework skills to "re-chip" the board with some NOS DRAM ICs.
  16. techknight

    SE/30 Xceed greyscale adapter cloning thread

    Well I was thinking along the side of driving the analog board from the video card, not sync the video card to the analog board. Seems backwards to me.
  17. techknight

    SE/30 Xceed greyscale adapter cloning thread

    Yea, I just saw your diagram. I am just trying to figure out why its this convoluted.
  18. techknight

    SE/30 Xceed greyscale adapter cloning thread

    Yes I am, but I dont have the time currently to take a project like this on, at the moment. So Bolle is your man. Once its in some sort of schematic, and I can look at the PAL equasions, I may be able to figure out how to modify the design to 512x342 that fits the compact mac, as electronics engineering is my day job.
  19. techknight

    SE/30 Xceed greyscale adapter cloning thread

    Ok, the PDS as far as I am aware has no video signals present. However, the entire video circuit is sync with the motherboard clock signals, so you can use the clock signal present on the PDS slot as the timing source for both HSYNC and VSYNC. As far as reverse engineering the PCB back into a schematic, thats easy. and its non-destructive. I have been on a 68K project this year (not mac) that I reverse engineered 4 boards back into schematics.
  20. techknight

    SE/30 Xceed greyscale adapter cloning thread

    Oh I didnt know the equasions were available. So there is nothing stopping anyone from cloning this card then basically.
  21. techknight

    SE/30 Xceed greyscale adapter cloning thread

    That particular graphics card may not have an ASIC as in a single chip, but it might as well be just as complex. Sadly, in the photos, I see multiple registered PAL/GAL devices which basically form up an ASIC in a logical sense. They would have to be decapped/reverse engineered unless you study timing diagrams and can build new logic based off of that... Not easy IMHO. They serve a pretty powerful purpose, such as refreshing the RAM as needed (Not sure if its dual port VRAM or standard DRAM, i have seen both used). As well as controlling DTACK to insert wait states if the memory is single-port, doing a read cycle via the rasterization timing circuit, while the CPU is trying to read/write the RAM at the same time. So DRAM access requests are interleaved between the CPU and the RAMDAC. Its easy to probe and brute force combinational PALs back into logic verilog code, I have done this many many times. But registered devices, Nope....
  22. techknight

    FPGA Mac

    It's been done in a way. Steve chamberlain started it as a proof of concept with Emulating a macintosh plus on an FPGA. Might want to check out that project.
  23. techknight

    SE/30 video redraw problem

    Ive seen the PAL sets go bad a couple times, usually resulting in missing vertical, or horizontal drive. If your address lines to and from the muxes are good, chances are the muxes are bad. They are failing left and right in the standard RAM stages too.
  24. techknight

    SE/30 Xceed greyscale adapter cloning thread

    FPGAs can take over everything the main chip did, as long as you know the logic behind it. using SDRAM coupled to the FPGA would work fine for the video speeds this thing is working at.
  25. techknight

    SE/30 video redraw problem

    Your missing address lines/signals to the video memory from the main system bus. the framebuffer output is able to see the video memory as its drawing the standard bars as uninitialized framebuffer space. So you need to trace all that down, as well as checking the PALs. You could have a bad one.
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