NEO-257: Difference between revisions

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


[[Category:Chips]]
[[Category:Chips]]

Revision as of 09:49, 7 May 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 LOW, B if HIGH.
  • Some pins marked as ground could be "enable" pins