(Expand for Errata) Previously, we looked at the 8×8 LED Matrix. We noted that, since it needs 16 pins to power, we’ll have to sacrifice quite a lot of pins on the microcontroller. I left this as an open question at the end of that episode, which you can watch here →
In this video, we try to look for ways to cut down on the number of pins, through use of our trusty 74HC595N shift register! We first looked at this nifty little component, which helps store one byte of data, in this video →
By combining two shift registers with the LED Matrix, we can eliminate almost all of the pins used to drive the matrix. What’s even better is, the first shift register can drive the second, reducing our pin count down to just 3.
Want to see the code? Downloads are here:
To download, click “Download” on the left sidebar, and select “Download Repository”.
= ERRATA =
Please note the mistake at 9:10 – In the diagram, the shift and store pins have been reversed. The store pin should be above the shift pin. Thank you very much to Joshua Thyer for pointing out the error!
= 0612 TV =
0612 TV, a sub-project of NERDfirst.net, is an educational YouTube channel. Started in 2008, we have now covered a wide range of topics, from areas such as Programming, Algorithms and Computing Theories, Computer Graphics, Photography, and Specialized Guides for using software such as FFMPEG, Deshaker, GIMP and more!
Enjoy your stay, and don’t hesitate to drop me a comment or a personal message to my inbox =) If you like my work, don’t forget to subscribe!
Like what you see? Buy me a coffee →
0612 TV Official Writeup:
More about me:
Official Twitter:
= NERDfirst =
NERDfirst is a project allowing me to go above and beyond YouTube videos into areas like app and game development. It will also contain the official 0612 TV blog and other resources.
Watch this space, and keep your eyes peeled on this channel for more updates!
—–
Disclaimer: Please note that any information is provided on this channel in good faith, but I cannot guarantee 100% accuracy / correctness on all content. Contributors to this channel are not to be held responsible for any possible outcomes from your use of the information.
Nguồn:https://madisonrep.org/
Xem Thêm Bài Viết Khác:https://madisonrep.org/cong-nghe
Great video, I like how you progress from an initial idea to a more optimized design. One question though – at 8:34 the resistors are row based yet at 11:00 your pictures shows them column based.
This is an awesome video thanks for sharing all the good information,
If i want to use an led stripe , do i need to follow the same concept?
very clear
Thanks man! Now i got to know many others are unnecessarily making this concept complicated. Its very difficult to write control code if you are making a 20 X 20 led matrix, the binary for 20 will be very big and you cant use Int as you exceed its limitation, so I used Float. But yours differential control for each shift register is awesome!
K
Could you use this scheme to control a 9px row x 368 column matrix? I'd even be willing to leave a column on the table if I could do this with 47 shift registers, and only 3 data pins.
(128 >> i) can be replaced with (1 << (7 – i)) which is preferred for readability.
So I'm making a custom Matrix, and I need it to be an 8×9 matrix, I assume I will have to make use of another shift register right?
is there a zip file to program ?
Thank you so much!
Propbably a ridiculous question but how do you know which side is the rows on the led matrix and which side is the columns?
Can email you I had a few questions from you
at 9:10 you show a pin schematic for the 74HC595N chip labeling 5th pin on the right Shift, and the 6th pin on the right Store.
but @ 10:06 when you show the 2 chip wiring diagram you switch the Shift and store pins coming from the Arduino signal.
I was just wondering if this was a mistake or something?
Love the content and thanks for the help so far!
very helpfull. tanks
Thank you so much for this explainining
I built my own 8*8 matrix, and wired it as shown, when I uploaded the code, all of the LEDs were lit. Could you point me in the right direction to debug the issue? And something that I wasn't quite clear on from your video, should enable and reset be pulled high or low?
Maybe a noob question but…where do I connect the data, store and shift pin from the shift registor to the arduino ?
Fantastic explanation. Very detailed and consise and very clear to understand. One of the best that I have seen so far on youtube. Keep up the exellent work.
I have a question for you. If I only have resistors on the grounds can I light up all the LEDs at once or will it have to be scanned instead? do i choose the resistor based on 8 Leds in parallel or do i base the resistor on 1 led? For example if the grounds are on the columns and i try to light the whole column vs one led in that column. to light the whole column will i have to scan or can i just send power to all rows ? 8 leds would be on going thru one resistor..
Good mourning, please can I use this code in pic 16f877a
More tutorials my boss
Good tutor. More power to your elbow
excellent video, you make it easy to understand ! Your efforts are greatly appreciated – thank you!
Your video was the only one that helped me understand this! Thank you for making this video.
very good explanation! i understand now. but now i donthave idea how that led matrix can show running text. pls make video how to do running text use led matrix. i appreciate it. Thank you!
is there a schematic available somewhre where to read how you connected the 595 with the row and col of the matrix?
Thank you
wery good explanation thank you
Nice video! There's one thing that I want to ask: can I control one single LED and let it blink, which is a pwm signal output by the register.