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Apple IIe Tech Note #5 /INH Line
- Subject: Apple IIe Tech Note #5 /INH Line
- From: a2retro <a2retrosystems@gmail.com>
- Date: Thu, 20 Sep 2012 08:50:52 -0700 (PDT)
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Hi I was reviewing the /INH technote for the IIe and I was confused
about the operation of the sample circuit at the end of the tech note.
1) The 2159 ram chip (which I can find no trace of on Google) shows an
active high for the write enable - should it not be active low like
the output enable?
2) READDIS actually disables both reading and writing to the RAM?
3) If READEN is active I follow how a write from the A2 R/W signal
activates the INHIBIT but I don't follow how a READ enables it?
Any insights would be appreciated.
Glenn