Keypad matrix decoder

Discussion in 'Homework Help' started by cherry pie, Sep 1, 2011.

  1. cherry pie

    Thread Starter New Member

    Sep 1, 2011
    Hi, I have to design a keypad matrix decoder system. The system consists of a keypad matrix, a 4-bit ring counter as a synchronous sequential circuit and a HEX to 7-segment display. Then the three components need to be integrated.

    I'm facing trouble designing the ring counter. Could someone please suggest how I go about the same? The counter has to produce sequences 1000, 0100, 0010, 0001, 1000, 0100,.... and should be connected to the column lines. There should also be an input Dv (which is the Enable input of the 7-segment decoder) along with the clock signal.

    Can anyone please upload the schematic of what the ring counter should look like for this case?

    Thank you :)
  2. bwana

    New Member

    Sep 1, 2011
    CD 4017 with output #5 tied to reset.
    In the case you decided to use a microprocessor, a shift- right cycle.