NEO-257: Difference between revisions

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== Pinout ==
== Pinout ==
Information provided by Channelmaniac.


[[File:Neo-257_pinout.png]]
[[File:Neo-257_pinout.png]]

Revision as of 07:10, 8 February 2011

Quadruple 74HC257 2-to-1 multiplexer with common select line, making 16 switches in one chip. Used in dual slot MVS systems to select one of the two C ROM (and S ROM ?) buses.

Select signal comes from one of the "SLOT" outputs of NEO-F0 ?

Pinout

Information provided by Channelmaniac.

File:Neo-257 pinout.png

  • A*,B*: Inputs
  • Y*: Outputs
  • Select: Output A if high, B otherwise.
  • Some pins marked as ground could be "enable" pins