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author: Oldrich Pecak
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# Hazards, advanced circuits

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## Hazards
- glitches caused by physical delays in circuit
- can be analysed in karnaugh map
- problematic for edge-triggered circuits
- usually not visible by human eye

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## Multiplexers
- circuit for switching multiple inputs into single output
- usually 2 groups of inputs:
    - multiple signal in
    - select input
- demultiplexers are the other way around

- Let's build basic multiplexer

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## Using multiplexers as LUTs
- you can implement look up tables (LUTs) using muxes
- commonly used technique to implement various logic functions
- multiplexers/demultiplexers are common component
    - 74x151 - 8bit multiplexer
    - 74x352 - 2x 4bit multiplexer

|A|B|C|X|
|-|-|-|-|
|0|0|0|0|
|0|0|1|0|
|0|1|0|1|
|0|1|1|1|
|1|0|0|0|
|1|0|1|1|
|1|1|0|0|
|1|1|1|1|

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# Unrelated bonus!

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# Homework
- design and build/simulate a 7 segment display driver
- do not use common 74xxx or 40xxx series 7 segment converter!
- you can do it either in Digital (recommended) or on a breadboard
- input: 4bit number
- output: logical values for the A-G segments of the display