Posted By
BushRat
on 2003-02-10
|  Kinda figured...
Sounds like a do-able project. I don't have a spare SX keyboard cable, but I can trace the pinout for you, if it isn't already available on the net. You may just have to hardwire a cord for it. Yeah I'll just send a 1581. You are talking (in the 156x series) a unit similar to the outboard drive for the Amiga?
My "real" plus4 has a dual Ntsc/Pal kernal in it using os93. Did an article on it once, for Jack Vander White it should be on that first CD, it uses a 27256 eprom that switches like Jiffydos. Dpdt slide switch selects the rom and switches one leg of the appropriate xtal for ntsc/pal... which is why I sent the pal xtal (didn't know if you had one). I experimented, once, using a 27512 (which is as big as the Promenade could handle) and put a couple of operating systems on a chip. It worked just fine, allowing you to switch two kernals in the lower bank and two in the upper bank. The drive signal on the xtal seems to be hefty and forgiving enough to allow up to 5 or 6 inches of wire to the xtal switch. I never did check with a freq meter if there was any drift with extra wire, but I never have a problem with it locking to the xtal ntsc or pal. Let me know how that project progresses.. if it is Top Secret, then email me.
I'd sent Csabo the Elder files from the CD, since you were mostly interested in the Ntsc side of things. He might as well have the Euro stuff (Pal). I'd noticed that SVS was asking about him an his collection. The Elder stuff I had was a fair chunk of it. Didn't think you'd mind that...
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