Any idea is appreciated. Expert, experience and circuit builder

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Exjay

Joined Nov 19, 2015
166
I want to design a circuit as in the attached image. The block diagram in the image is not yet complete. I want the up and down button to switch between the four 7-segment display, as in when am done controlling one 7-segment I can switch to other 7-segment. At the same time, I want the 7-segment display the switch is controlling to be blinking to show which 7-segment the switch is controlling. I also want when power is off the number at the four 7-segment display to be retained when power is restored
 

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danadak

Joined Mar 10, 2018
4,057
A micro could give you buttons using Capsense with debounce, a pad on a PCB, or if you
want to use mechanical buttons debounce capability.

Micro easy to do counters.

What is max count speed, just the button presses ?

Micro could handle TFT Graphic or LCD Char display or OLED Graphic.....

And lots of other stuff. Like analog capability in case you need that.


Regards, Dana.
 

absf

Joined Dec 29, 2010
1,968
Let me make your block diagram clearer so every can see. I also added in the "channel selection logic" block and the 4 or 2 switches for channel selection.

rotated_tmp-cam-912121619.jpg
 

absf

Joined Dec 29, 2010
1,968
I want to design a circuit as in the attached image. The block diagram in the image is not yet complete. I want the up and down button to switch between the four 7-segment display, as in when am done controlling one 7-segment I can switch to other 7-segment. At the same time, I want the 7-segment display the switch is controlling to be blinking to show which 7-segment the switch is controlling. I also want when power is off the number at the four 7-segment display to be retained when power is restored
1.)I want the up and down button to switch between the four 7-segment display.
2.)controlling one 7-segment I can switch to other 7-segment.
3.)the 7-segment display the switch is controlling to be blinking to show which 7-segment the switch is controlling.
4.)when power is off the number at the four 7-segment display to be retained when power is restored.

You need 4x 40110 up/down counter to SSD, 1x 4052 multiplexer to fulfill the basic function.

To satisfy #3 you need a 555 timer with 4 AND gates controlling the CC of the SSD. The AND would be controlled by a 2 to 4 decoder (74HC139) with 2 bit inputs.

To satisfy #4, you need battery backed memory for the counters which is not easy using discrete logic design. And the cost will shoot up due to this function.

I would have use a 18 pin PIC to realize the design using EEPROM to save the setting before power down. Instead of making my hair turn white to design in discrete logic.

Allen
 
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