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Topic: Create 10*10 rgb led matrix (Read 1 time) previous topic - next topic

Stevemoretz

Jan 25, 2018, 10:40 am Last Edit: Jan 25, 2018, 01:37 pm by Stevemoretz
(I don't want to use pre assembled led matrixs).

The goal is to make a 10*10 matrix to control 100 Rgb leds individually.
I DON'T have enough pins on my arduino so I started to think using 2 pwm pin extenders each 10 pins would be the answer.

 I checked 74HC595 out brilliant it's so cheap but it doesn't support pwm...

The purpose is to use a cheap module with the least use of arduino pins.

Tnx Steve.

wvmarle

Shift registers such as the 74HC595 are really cheap, they go for well under USD 0.50 a piece (DIP package; SMD packages are cheaper).
Quality of answers is related to the quality of questions. Good questions will get good answers. Useless answers are a sign of a poor question.

Stevemoretz

I checked it out Tnx brilliant it's so cheap but does it support pwm I need to control Rgb leds and how many pins does it need and how many pins does it extend?Tnx I just could get the price form a shop.

Wawa

100 RGB LEDs = 300 control pins = 38 * 74HC595 chips (plus the needed buffers).
That could look like a big mess.

Addressable RGB LEDS is an easy/clean solution, and maybe cheaper in the end.
No other chips needed. Just one resistor and one cap.
Leo..

westfw

The han Ron ht1632c chips did an adequate job of handling the 384 lights,  arduino folk ran with them all soerts of displays.

dave-in-nj

#5
Jan 25, 2018, 01:06 pm Last Edit: Jan 25, 2018, 01:24 pm by dave-in-nj

for - 64 individual LEDs.
MAX7219 daisychainable
These are for LED displays, so I believe are not dimmable
past halfway down the page
http://www.crossroadsfencing.com/BobuinoRev17



dave-in-nj

#6
Jan 25, 2018, 01:15 pm Last Edit: Jan 25, 2018, 01:26 pm by dave-in-nj
too much X/Y in this problem
100 RGB LEDs ?
on / off
I need to make the matrix
I need to [two] pin extenders each 10[pins ?] to make my own matrix
and
" I checked it [ 74HC595] out Tnx brilliant it's so cheap but does it support pwm..."

========
Can I assume you want :
the goal is a 10x10 matrix of RGB LEDs ?
question is what is the best way ?
requirement : use the least pins on an Arduino



Stevemoretz

100 RGB LEDs = 300 control pins = 38 * 74HC595 chips (plus the needed buffers).
That could look like a big mess.

Addressable RGB LEDS is an easy/clean solution, and maybe cheaper in the end.
No other chips needed. Just one resistor and one cap.
Leo..
Well I thought using the matrix algorithm you just need two shift registers.10*10=100
Addressable Rgb leds wow!that looks cool!Never heard of that but all I found all the Google was strip leds which I don't need it to be strip.So a link would be great Tnx.

@westfw
ht1632c this looks to be a display driver I don't think so if display drivers can support pwm can they?I don't know how to work with them.i found a version
32x4 LCD driver
Costing 13 dollars I don't know for sure does it mean I can control 128 Rgb leds?13 dollars is fine for this I guess please explain more Tnx.

@dave-in-nj
Thank you so much but the whole point of this question is to get Rgb leds work so dimming is definitely needed . Tnx for the edit yeah you're right I need to change the topic title and thing I'll do it Tnx.

dave-in-nj

The han Ron ht1632c chips did an adequate job of handling the 384 lights,  arduino folk ran with them all soerts of displays.
32 x 16  but we live in a 10-digit world......  10 x 10
I think the same folks who did this also makes hot dogs in 10 packs and rolls in 8 packs.

dave-in-nj

Addressable Rgb leds wow!that looks cool!Never heard of that 
google neopixel 
and  WS2812

Stevemoretz

32 x 16  but we live in a 10-digit world......  10 x 10
I think the same folks who did this also makes hot dogs in 10 packs and rolls in 8 packs.
I don't know man it was in the information of buying models here's the whole
Features:

Operating voltage : 2.4V~5.2V
Built-in 256kHz RC oscillator
External 32.768kHz crystal or 256kHz frequency source input
Selection of 1/2 or 1/3 bias, and selection of 1/2 or 1/3 or 1/4 duty LCD applications
Internal time base frequency sources
Two selectable buzzer frequencies (2kHz/4kHz)
Power down command reduces power consumption
Built-in time base generator and WDT
Time base or WDT overflow output
8 kinds of time base/WDT clock sources
32x4 LCD driver
Built-in 32x4 bit display RAM
3-wire serial interface
Internal LCD driving frequency source
Software configuration feature
Data mode and command mode instructions
R/W address auto increment
Three data accessing modes
VLCD pin for adjusting LCD operating voltage
HT1621: 44-pin LQFP package
HT1621B: 48-pin SSOP/LQFP packages
HT1621G: Gold bumped chip

Tnx checked out WS2812 100 leds cost around 34 dollars which is not that good but not that bad.Tough the neopixel costs too much more.

Stevemoretz

Found a cheaper WS2812 100 would be 26 dollars.Just a question how am I supposed to address WS2812 and how many pins does it need?is it on i2c?

Grumpy_Mike

#12
Jan 25, 2018, 02:15 pm Last Edit: Jan 25, 2018, 02:16 pm by Grumpy_Mike
Quote
how many pins does it need?
One.
A Neopixel is simply Adafruit's trade name for a WS2812.

They are addressed in software a bit like a shift register. You have an area of memory with each byte representing one colour component of one LED. When your code has set these bytes then the whole lot is sent over one wire for the LEDs to pick up.

Stevemoretz

One.
A Neopixel is simply Adafruit's trade name for a WS2812.

They are addressed in software a bit like a shift register. You have an area of memory with each byte representing one colour component of one LED. When your code has set these bytes then the whole lot is sent over one wire for the LEDs to pick up.
Cool! Just the last question is, does there exist any Addressable Rgb leds cheaper than WS2812?
Tnx everyone for the guidance really helped me and other ppl will read this thread.

Grumpy_Mike

Quote
does there exist any Addressable Rgb leds cheaper than WS2812?
Not genetically but you might find something on eBay. The WS2812b has the controller and LED built into one package. Their are other strips with separate LEDs and controller but most of them control the LEDs only in groups of three, but per LED they are cheaper.

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