implementation of a 5 input - 6 output truth table

Discussion in 'General Electronics Chat' started by hunterage2000, Jan 18, 2013.

  1. hunterage2000

    Thread Starter Active Member

    May 2, 2010
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    I have a 5 input - 6 output truth table I want to implement. I have had suggestions of using a PLA or PROM. I have looked up a TIBPAL16L8-15CN and the datasheet says hardware and software is needed to set the truth table.

    Can anyone tell me where I can get these? I have looked on the web but cant find anything. The data sheet shows a logic diagram which I have no clue what it means or I would go about programming it.
     
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  2. kubeek

    AAC Fanatic!

    Sep 20, 2005
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    You would need a PAL programmer for that chip.
     
  3. hunterage2000

    Thread Starter Active Member

    May 2, 2010
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    Are these programmers expensive? Does a ROM need a programmer as well?
     
  4. kubeek

    AAC Fanatic!

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    No idea about the price, but I guess you should be able to find something on ebay.
    I think programming a fuse-link ROM can be done by hand, if the datasheet shows the programming process.
     
  5. Papabravo

    Expert

    Feb 24, 2006
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    Data I/O used to make the "de facto" PAL programmer called the 29B. It had a series of interchangeable heads and cost about $10,000 for the base unit, 4 or 5 plugins and the ABEL software for entering equations and creating the fusemap.

    Each of the intersections represents an intact poly-silicon fuse. By applying a high current to the individual fuses you can make them open. The remaining intact fusses represent the minterms in a SOP (Sum of Products) expression.

    I'm pretty sure there are cheaper alternatives today, but MSI has largely been replaced by the FPGA so good luck.
     
  6. hunterage2000

    Thread Starter Active Member

    May 2, 2010
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    I could make the truth table from gates but theres loads. My truth table has 5 inputs and 6 outputs with 32 combinations. Im not sure if I'm asking the right questions to implement this.
     
  7. kubeek

    AAC Fanatic!

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    Maybe something more modern like a CPLD could do the job better? But I am not sure if it will be able to do the job without a clock.
     
  8. hunterage2000

    Thread Starter Active Member

    May 2, 2010
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    Can these CPLD#s operate as stand-alone or do I need to use a Microcontroller?
     
  9. kubeek

    AAC Fanatic!

    Sep 20, 2005
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    Once you program them they act like a standalone circuit, and the larger ones should be able to do some pretty complicated logic.
     
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