Logic Signals



  There are a number of different systems for representing binary information in physical systems.  Here are a few.


  • A voltage signal with zero (0) corresponding to 0 volts and one (1) corresponding to five or three volts.
  • A sinusoidal signal with zero corresponding to some frequency, and one corresponding to some other frequency.
  • A current signal with zero corresponding to 4 milliamps and one corresponding to 20 milliamps.
  • And one last way is to use switches, OPEN for "0" and CLOSED for "1".
  • (And there are more ways!)