DOT-matrix display(LED matrix) points for a good design.

[huzaifahm]

led dot matrix pld drive

ah.ok..
back to my project...how can i elimanate shadowing? im driving my collum with a shiftregister,with latch and my row with 7port and a transistor,,

This flickering can be removed in programming. Following is the pseudo code I follow:

For rows 0 to 6{
FillColumnBuffer(rowID)
TurnOFFRows(all)
ClockDataInCols()
TurnOnRow(rowID)
Delay()
}
You will have to be accurate about delay. And donot process anything else when clocking data in. You have to minimize the time between turning all rows OFF and turning the next row ON.

Regarding brightness control, You will have to introduce PWM of some sort, which will give 1 to each row in pulses. Usually, Instead of pulses, I turn each row on fully for like 8ms(assumed value) and then I turn off all rows. When you introduce PWM, it will use the same 8ms time, but instead of putting row ON full time, it will send pulses to turn leds on and off. The more the pulses, the lesser the brightness. That is why without using PWM will have the most brightness.

Do you need anymore help?

 

[leoren_tm]

led matrix board design

Do you need anymore help?

i realy need help. i just made my prototype but i have now problems...i could not reach the required voltage, that is why its dim...i have problem on my row driver(5x7)...im using a darlington pairs, can you suggest a flowdiagram? and im coding it on assembly.

 

[huzaifahm]

displaying data from keyboard to dot matrix

Follow this:

https://attiny.com/dotmatrix.htm

I will post some technical talk later after you have reviewed above website.

 

[aderich]

scan led using 4094 electronics

i will think it to be a simple manipulation of the previous circuitry.
the use of a 748cf95a shift vregister will give a clear guide to your quest

 

[leoren_tm]

led matrix design shift registers

Follow this:

https://attiny.com/dotmatrix.htm

I will post some technical talk later after you have reviewed above website.

quiet busy..ill read it and ask some question..thanks man..

 

[qingwei_cui]

direct drive led matrix

thank you for your share

 

[zuisti]

led matrix elektor

My MMD project (working in Proteus ISIS) was upgraded for char scrolling (switchable, the speed too), the source is converted to C (MikroC) and PicBasic (Proton+) too.
A newer ZIP is uploaded by me:

 

[raghun]

matrix led module

where can i tutorial about led matrix display

 

[leoren_tm]

led dot matrix circuits

after reading it..i was confuse on how did you display a running text??
at what part of it? if displaying it 20times....uhmmm...if your displaying a running text, you would have a problem if it would be design on just accepting a character...and display it...and did you map it??why ASCII??how did you do it?

 

[sohail_akram]

ic 4094 dot matric

THis is bundle of moving message circuits and softawres

 

[valeryi]

led matrix driver transistor

Thanks

 

[OBIALOR]

at89c.110mb.com

sohail,it seems you have good project on moving sign display for the forums...

 

[pcup]

dot display tutorial

Please help me to drive using I2C communication this Single Colored Led 5x7 dot matrix multiplexed with MAX6953.

Thank you

 

[leoren_tm]

4094+dot matrix

first constract the circiut...then...post it...maybe someone will help you code it..or i can help you..

Added after 1 minutes:

THis is bundle of moving message circuits and softawres

ill try reading it...anyway..i already design one..ill post it out if its finish..

 

[wizardgrt]

dot matrix project in proteus

This is a little older solution for a dot matrix display, but it works. It is based on AT90s2313/ATtiny2313 atmel microcontroller. Hope you'll find it useful

 

[wizardgrt]

led dot matrix circuit

...and another Atmel DOT matrix display project...

 

[valeryi]

led matrix simulation proteus

very good info thanks a lot

 

[leoren_tm]

circuit design for led display matrix

THis is bundle of moving message circuits and softawres

am i right? most of the program on your upload, are from this forum also...i think you just compiled it...correct me if im wrong..
thanks for the effort

 

[OBIALOR]

dot matrix 128*64 display tutorial

hello wizardrt let me try to see ur file and if it is helpful ,that will be very good

 

[joet_x]

displays led matrix

nice design, i will try it.. but how we can update data from pc at external eeprom?