7 segment display with IC4026 and NE555 timer control

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Hello,
I have to make a circuit using IC4026 and 555 timer with 3 switches : one that pauses the counting, one that hides it and one that resets it. I'm having problems with the last two.
I have joined a picture of my circuit on proteus isis.
I'll be very grateful if you could help me.
 
Attachments
  • Proteus schematic of a 555 timer (U1) clocking a 4026 decade counter (U2) that drives a common-cathode seven-segment display, with R2, R3, C1, C2 and C4 as timing components.
    7segments4026NE555.PNG
    3.9 KB · Views: 653
ranai said:
I'm having problems with the last two.
What did you try so far, where did you get stuck?

The IC should have some data sheet explaining how to reset the counter.
 
I modified the circuit, now I can pause and reset the counting.
what I would like to do is hide it when you push a button but still counts until you let go of the button
 
Attachments
  • Proteus schematic of a 555 timer clock driving a 4026 decade counter into a seven-segment display, with two push-button switches for pause and reset, and R1 100k, R2 100k, R3 68k, C1 1nF, C2 and C4 10uF.
    7segPauseReset.PNG
    26.8 KB · Views: 1,084
Last edited:
mfb said:
What did you try so far, where did you get stuck?

The IC should have some data sheet explaining how to reset the counter.

I changed the circuit, now I can reset and pause the citcuit .
What I would like to do is hide the count when I push a button while it still goes on until I let go of the button then the display is on again.
thank you for your help.
 
Attachments
  • Proteus schematic of a 555 timer astable oscillator (U1) clocking a 4026 decade counter (U2) driving a seven-segment display, with push-button switches for reset and pause.
    7segPauseReset.PNG
    28.7 KB · Views: 840
That's what pin 3 DEI(display enable input) is for. A low at this input turns off the display output.
 
Janus said:
That's what pin 3 DEI(display enable input) is for. A low at this input turns off the display output.
hello jamus,
I tried doing that by shorting the supply to ground but I get yellow squares does that mean that there is an error ?
 
Attachments
  • Proteus schematic of a 555 timer astable clock feeding a 4026 decade counter that drives a seven-segment display, with R1 and R2 100k resistors, R3 68k, C1 1nf and C2 and C4 10uf capacitors.
    error3.PNG
    38.3 KB · Views: 1,017
Why do you want to create a short circuit between power supply and ground?
Potentially damaging your power supply should give an error, indeed.
What does that have to do with the DEI input?
 
Why would you try pulling the supply to ground? You only need to pull pin three to ground.(without effecting the rest of the circuit).
 
I added a switch between pin 3 U2 and the supply.
So the display is on when the we push the switch and it is off when youlet go of the switch.
Is there any way without using logic gate NOT to have it display normaly and to turn off the display output when we push the button ?
 
Attachments
  • Schematic of a 555 timer clock feeding a 4026 decade counter driving a seven-segment display, with RESET, HIDE and PAUSE switches, resistors R1 to R3 and capacitors C1, C2 and C4.
    PauseResetHide.PNG
    5.1 KB · Views: 679
ranai said:
I added a switch between pin 3 U2 and the supply.
So the display is on when the we push the switch and it is off when youlet go of the switch.
Is there any way without using logic gate NOT to have it display normaly and to turn off the display output when we push the button ?

Connect a resistor between supply and pin three and your switch between pin three and ground. With the button released, the pin is pulled high. When the button is pushed, it is pulled low, but the resistor prevents the supply from being shorted.
 
Janus said:
Connect a resistor between supply and pin three and your switch between pin three and ground. With the button released, the pin is pulled high. When the button is pushed, it is pulled low, but the resistor prevents the supply from being shorted.
Thank you very much Janus !