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About techknight

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  1. techknight

    VRAM SE/30

    You would have to create an oversampling, something that cant be done with the CRT without cranking up the frequency.
  2. techknight

    SCS2SD - Mac Plus bootable solution

    youll see a diode foot print behind the SCSI connector, thats where you put the diode. it feeds term power out the db25.
  3. techknight

    MacToTheFuture SE30 Network Card Driver

    I think you pretty much beyond all of us here currently, at least when it comes to apple dev. There are a few guys here that do it, but only one or two of us that have done drivers.
  4. techknight

    145B LCD recapped with tantalums

    Yea itll improve the image quality by an order of magnitude. Main reason is the passive matrix LCD requires a high driving voltage. around 40V or so for the sinusoidal signal to keep the crystals from developing a memory effect. If the caps are bad, it distorts that voltage and signal, seriously compromising the image quality.
  5. Peripheral card developers could get schematics from Apple under NDA. Thats how I obtained the portable schematics which are now public of course. It came from a defunct RAM manufacturer for the portable. I still have the PALASM documents, and some schematics, etc that I have NOT shared.
  6. techknight

    How to spot a counterfeit Capacitor

    Yea.... That member isnt here anymore, so unless someone else picks up the ball, thatll never happen.
  7. techknight

    ROM Interleaving tool?

    my german skills are non-existent. I ended up throwing together a quick little program to do this. Been spending the past week or so disassembling and reverse-engineering a 68010 VMEBus based machine, trying to make heads or tails of it. Not getting too far.
  8. I guess everyones hearing tolerances are different. When I was a kid, I could tell if a TV was left on all the way across a room. But it was never really painful. But during those same days, I could never listen to FM stereo either because I could hear that 19K pilot tone. Now I am lucky to hear above 14khz before it all blends into my tinnitus. These days I hear the old school "tv flyback running" 24/7. Called Tinnitus. LOL.
  9. techknight

    ROM Interleaving tool?

    I would hate to write one if I dont have to, but is there a quicky little tool somewhere that can take the LOW/HIGH images of ROM and interleave them back into a single ROM image? I vaguely recall a thread about that but ill be darned if I can find it.
  10. techknight

    MicroMac Performer SE Mod

    Without seeing the schematic and the GALs actual native boolean logic, its just a blindfolded shooting match guessing game. The GALS functions are basically to emulate the E/VPA/VMA system, maybe some simple address decoding for a DeclROM, and the bus master takeover, using the Bus Grant, Granted to take over the 68000 before it will release the 030 from running.
  11. techknight

    MicroMac Performer SE Mod

    Yea I know. It took me awhile to figure it out, but once I did I began to understand it. I needed to if the RAM card was ever gonna work.
  12. techknight

    MicroMac Performer SE Mod

    68K communication is asynchronous by nature. it could run at 500Mhz and the bus at 8Mhz, it wouldn't matter. You would have a shit ton of wait states but it would work. The catch is the E/VPA/VMA of the synchronous bus. It would need to be locked to the system bus if the system uses these, and the Mac does. the VIA, etc use it. So there would be PALs/GALs that interface with this, and thats that.
  13. techknight

    MicroMac Performer SE Mod

    8 goes into 32, but not 33 or 25. Not sure how they can get 8 from either of those. It would require a PLL.
  14. techknight

    MicroMac Performer SE Mod

    If they are generated separately, They dont. One has to generate the other, and they lock by phase, thats it.
  15. techknight

    MicroMac Performer SE Mod

    According to some of the articles I found, it was mentioned never to use this circuit design. Probably why have never heard of it. So you dont need a GAL here. Just use a clock multiplier IC and form a small circuit around it. Like this one: https://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?catalogId=10001&langId=-1&freeText=pll-clock-multiplier&storeId=10001&productId=2054361&krypto=4We6orF%2FQq5lWZdXyYEvrdAYAdhOJj8HYljOOKxHoLoVxQzggZZcSX2XGmFUnAG0lQR7Dh4ZNJ0lR8bZ3KHdN3xKnbBF4dPsto26knu2gUY%3D&ddkey=https%3AStoreCatalogDrillDownView