PIC Oscilloscope Clock

For those are not into electronics, you must know that an oscilloscope has basically only one timebase to move the spot horizontally from left to right with the same intensity. The vertical deviation is function to the input voltage. You understand immediately that you can't directly display 7 segment digits, because you can't move the spot from right to left.



By using X/Y mode, where the spot is controlled on two axes by two different voltages, it is possible to draw a picture (as in the examples mentioned above), but a fast digital to analog converter with two channels and at least 8 bits of resolution would be needed.

So we have to deal with a spot that always goes from left to right in the same period of time.
If we want to have a 7segment-like display, we have to draw :

vertical segments : easy to do, just change voltage up and down quickly a few times.
horizontal segments : easy to do, just set a voltage level and keep it as long as you need.

By using 2 PIC outputs and a basic R2R digital to analog converter, we can have up to four different voltage levels : 3 for the vertical segment, and another one where to put the spot when it is not in use to draw a segment.

But the problem is that a 7 segment digit may have up to 3 horizontal lines at a time (like 2, 3, 8, 9..) but we can draw only one during one spot deviation.
So we will have to cheat with retinal persistence and use multiple frames : since we can have only one vertical segment per period, three periods will be needed to draw a full 7 segment digit.

Supposing we want to display 12:34:56 on the screen :

During the first period, we will draw all vertical segments, and horizontal upper segments only :

As a game, I let you try to find out the spot trajectory.
Don't forget the rules :

you can't go backward
you can't clear the spot

But you can move so fast vertically that the eye can't see the spot moving.

The lowest line under the digits is not significant, it his the place where the spot is parked when not used to draw a segment.

Schematic Diagram:






Working Video



for more details see this LINK
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shshistiem
Wed Sep 12 2018, 10:58 PM
hii!! some1 please let me know how i ll get rfid code to 8051 by WEIGAND mode
DrNossberg
Tue Sep 11 2018, 08:09 PM
is there anyone here?
Mon Aug 27 2018, 07:30 AM
bun
Hello everyone´╝ü
Sat Jul 21 2018, 06:21 AM
Dibakar Bhanja Chowdhury
By using a 555 timer how can I expand the range of the mobile phone jammer? Please reply me asap
Sun May 20 2018, 10:01 AM
justinb
how to write and execute a program that read the keypad button and display the number on 7 segment on intel8051 at89s52 in assembly language?
Thu May 17 2018, 06:36 AM
HAMZA TAJ
sir iwant to ask about controller of three phase supply by using back to back thyristor instead of triac....will u give me some guideline?
Sat Apr 28 2018, 12:54 PM
ashutosh jain
IR Remote Switch using TV remote (RC5 Protocol) is not working properly. opp1 & opp2 is in problem.plz help
ExperimenterUK
Fri Apr 27 2018, 08:09 PM
@kaiserslautern Post in forum
Wed Apr 25 2018, 07:09 AM
kaiserslautern
Hello everyone, using software uart is a very good idea for a second serial port. Thank you so much. I would kindly like to know how to connect this port to the PC?
ExperimenterUK
Sat Apr 21 2018, 07:50 PM
This is a community site. Feel free to help anyone needing advice

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PCBindex
Fri Sep 14 2018, 02:45 AM
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ExperimenterUK Avatar
Posted By ExperimenterUK
Thu Sep 13 2018, 08:39 PM
First of all, by reading your reply, I abandoned m...
DrNossberg Avatar
Posted By DrNossberg
Thu Sep 13 2018, 03:49 PM
Hi, thanks you for your reply ^^ First of all, by ...
ExperimenterUK Avatar
Posted By ExperimenterUK
Wed Sep 12 2018, 12:12 AM
HiThere are several issues here.The original 8051 ...
DrNossberg Avatar
Posted By DrNossberg
Tue Sep 11 2018, 08:08 PM
Hello everybody!First of all let me explain some s...
ExperimenterUK Avatar
Posted By ExperimenterUK
Fri Sep 07 2018, 05:08 AM
The compiler thinks the micro doesn't have enough...
Sudhansudeep Avatar
Posted By Sudhansudeep
Fri Sep 07 2018, 02:59 AM
this is the build output message
Sudhansudeep Avatar
Posted By Sudhansudeep
Fri Sep 07 2018, 01:38 AM
Change the mobile number as [number removed] in t...
ExperimenterUK Avatar
Posted By ExperimenterUK
Thu Sep 06 2018, 08:56 PM
I don't know what the problem is, I get no errors....
Sudhansudeep Avatar
Posted By Sudhansudeep
Thu Sep 06 2018, 01:12 PM
the code is Attachment ...
Sudhansudeep Avatar
Posted By Sudhansudeep
Thu Sep 06 2018, 12:48 PM
the code is same as u sent me for 16 chars