Lesson 27 - VHDL Example 14: Multiplexing 7-Segment Displays

[@ns5253]

At 9:02 the video has entity mux7seg_top is ... end mux7seg I think mux7seg_top needs to be replaced with mux7seg.

[@electronichome1153]

Correct...

[@albertonavarrete8230]

I tried to implement this program in an altera board EP1C3, but the problem is the assignment of the digits for each display, no matter if I put x = X"1234", or if I put x(3 downto 0)

[@fardellp]

Surely with a common cathode (or common anode) this can be "energised" (I.e.cathode tied to ground or anode tied to Vcc). Only the individual segments need to be multiplexed. Why multiplex the common connection?

[@sunilkarki7024]

In Nexyus 3 board I only have 8 switches for inputs so how can I have 16 bit input?

[@tahmad20]

I tried this on my nexys3 and it works fine with some minor changes. Can someone please explain each line of code shown at about 9:30. From x = x"1234" to end case. I tried to modify the code and results are not as I expected. Obviously I did not fully get it. Thank you

[@chvrleshd]

please quick question , why is a seven segment display multiplexed?

[@firstlast759]

so you can display 1234 instead of just 1111

[@chvrleshd]

first last do you have a more technical answer?

[@mattvicent]

To display a number on a 1 digit display, you would need 7 outputs, to control each segment of that digit. To make a 4 digit display, you would need 7x4 outputs. That's possible, but not optimal, multiplexing allows you to use less outputs to do the same amount of operations.

[@chvrleshd]

Matheus Vicente thank you