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How To scroll led matrix ?

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mouzid

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led matrix

Hi,
The way to scrolling led display determines the power consumed by the whole circuit. I Wanna discuss this issue with you.
How scrolling is done generally for led matrix ?

I have a 8*40 led displayer.
Do I have do scrole it Column by column or pixel by pixel ?
Does pixel by pixel technique is possible and which technique is better the pixel by pixer Vertical scolling (of each column) or the diagonal scrolling ?
 

Tajinder Singh

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led matrix decoder

according to my experience there are possibly two methods for led matrix scanning

1. scanning by column
as u have shown in the diagram. in this pattern for each column is switched one by one.
This pattern require your column driver to be of high rating. as current of all the leds in one column may flow from single line. so for your 8*40 u need 40 driver connected with o/p of shift registers.
this method require less program complexity and scanning can be fast with less MIPS controller.


2. another method is scanning by row
in this whole row of 40 colmn is displayed at once.
u need to shift the data for one complete row and then latch it. then for 2nd ,3rd....8th.
this method require high current dirver on row sides only which is only 8. while on columns there is a load of 1 led only so u not need any driver on that side.
this method is more complex and require high MIPS microcontroller.
 
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betwixt

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scroll led

As your matrix is 8 dots high, it would be easiest to utilize the 8 bits directly from the port of a controller micro (via suitable drivers of course) to the rows. All you have to do then is address the columns individually with a strobe signal.

In a multi-character display you also need to be concerned about the refresh rate which would probably need to be 60 times per second or more. This might mean splitting the problem into smaller, more manageable sections, perhaps using a cheap micro per digit or small group of digits with the character information being distributed around the display by an other micro.

Another thing worth considering is the visual effect of scrolling the display if that is necessary. All multiplexed displays rely on persistence of vision to mentally draw complete character shapes, if the characters are in motion you either tend to get a sweeping effect if columns are driven or diagonal tearing if rows are driven. You would have to experiment to see which is least objectionable.

Brian.
 

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rushi53

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howto led matrix

mouzid said:
Hi,
I have a 8*40 led displayer.
Do I have do scrole it Column by column or pixel by pixel ?
Does pixel by pixel technique is possible and which technique is better the pixel by pixer Vertical scolling (of each column) or the diagonal scrolling ?

I have implemented this project and its working :)

I would suggest you to go for Scroll it Column by Coulmn

Visit this:
http://www.projectsof8051.com/projects/06-rolling-display-using-matrix-leds.html

Let me know if you need any more help

__________________
Thanks,
Rushikesh
www.projectsof8051.com
 

    mouzid

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mouzid

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rolling led matrix display

Thank you guys for your replies.
I still need some informations to scroll my led display.
The first information is how long (min and max) have I to switch on the led while scrolling? And How many time (also min and max) per second the columns have to be refreshed to avoid seeing leds switched off?
 

sn_burki

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led matrix circuit diagram

This is avery important issue, I tried my best but I think on this forum no body knows about moving message display alot or may not be willing to help in right ways??????????? I could not got the answer yet that If I am able to display a text on moving message display so how can I scrol it right or left????
Please if any one has any information about any book written on moving message display so please tell me the name or plz upload.

regards
 

john.l

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led matrix technique

hey guys, I am also looking for this project
thanks to you all.... it helped me a lot... :)
 

john.l

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led matrix scroll

does it require logic ics... like decoder. timer ?
please guide me built this... I am doing this as final year project....
 

rushi53

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led-matrix text scroller

john.l said:
does it require logic ics... like decoder. timer ?
please guide me built this... I am doing this as final year project....

the circuit which I developed does not contain timer
but yes, it contains 3:8 decoder.
Also it contains Latch ICs

Let me know if you need any more help
__________________
Thanks,
Rushikesh
www.projectsof8051.com
 

terminator.s68

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rolling displays how to

rushi53 said:
the circuit which I developed does not contain timer
but yes, it contains 3:8 decoder.
Also it contains Latch ICs
hello, thanks for providing this information
can you post circuit diagram here.... so that I can develop this circuit easily... thanks..
 

niekiran

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rolling display led matrix

how can i get 8051 simulator with motor,led,lcd..etc pls help
 

contactarman1

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Hi All thanks for providing this information
I have selected this project as my BTech project.
Till now I am working on simulation part.
Not yet decided with the actual circuit diagram.

My question is, should I use the ready blocks of Matrix LEDs
OR should I construct a PCB using individual LEDs ?

Plz guide me, thanks in advance....
 

rushi53

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contactarman1 said:
My question is, should I use the ready blocks of Matrix LEDs
OR should I construct a PCB using individual LEDs ?
Limitation of Ready blocks is their limited and fixed size

With PCB of ur own, u can construct Matrix of any size.
 

behnams66

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Re: led matrix circuit diagram

sn_burki said:
This is avery important issue, I tried my best but I think on this forum no body knows about moving message display alot or may not be willing to help in right ways??????????? I could not got the answer yet that If I am able to display a text on moving message display so how can I scrol it right or left????
Please if any one has any information about any book written on moving message display so please tell me the name or plz upload.

regards
hi you must shift the data troth the registers
when you need to move the data on the light board you first show the data for a
short time and then shift data to the next register and then repeat this period a
again ...
but this is depend on your design of the matrix led board ( row scan or column scan)
note : i live in iran and i cant write english very well ... i sorry because of my error in my handwriting .:D
 

rushi53

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