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R. Belmont
Cuckoo for IGAvania
Reged: 09/21/03
Posts: 9716
Loc: ECV-197 The Orville
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Re: Update @ Charles MacDonald's: Deco Cassettes (Feb.5)
02/06/12 09:58 PM


> I have never heard of "tristate" being used in this context... what does it mean?

It means that a given device is completely disconnecting itself from the bus, leaving the bus to "float" to random garbage values and/or be driven by some other device.

This is the origin of the "open bus read" commonly encountered in 8-bit computers; if you try to read an address where no device is mapped, *everything* goes tristate and the CPU reads back a semi-random value.

Edited by R. Belmont (02/06/12 09:59 PM)







Entire thread
Subject Posted by Posted on
* Update @ Charles MacDonald's: Deco Cassettes (Feb.5) SmitdoggAdministrator 02/06/12 05:06 PM
. * Re: Update @ Charles MacDonald's: Deco Cassettes (Feb.5) apeman  02/06/12 09:03 PM
. * Re: Update @ Charles MacDonald's: Deco Cassettes (Feb.5) R. Belmont  02/06/12 09:58 PM
. * Re: Update @ Charles MacDonald's: Deco Cassettes (Feb.5) apeman  02/07/12 07:54 AM

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