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Topic: Scrolling LED matrix display - Parola for Arduino (Read 143060 times) previous topic - next topic

shah123

Hi marco_c

This is really awesome.  Thanks for all the documentation and the support.

I was wondering if I could use the following cascaded into a 10 matrix display:

http://www.ebay.com/itm/1pcs-Red-MAX7219-LED-Dot-Matrix-Arduino-Microcontroller-Display-Module-Control-/271889207600?hash=item3f4ddc1130:g:z44AAOSwZd1Vblph

Do you think it would be possible to connect the input/output via jumpers for this module?

Your response will be highly appreciated.

Thanks.

marco_c

Quote
One issue I have observed is after about 15 minutes or so of running the Parola_Animate_Catalog example, artifacts would appear and certain pixels would remain lit until I hit the reset button which made them go away.
My best guess is that if your limit with no external power is 6 then you may be getting power supply issues. Does it work better with 4 or 5 and/or have you tried additional power?

I don't have any experience with nodemcu. I am surprised if PROGMEM does not work, but without knowing much about it I don't even want to guess.
Arduino Libraries http://arduinocode.codeplex.com
Parola for Arduino http://parola.codeplex.com
Arduino++ blog https://arduinoplusplus.wordpress.com

marco_c

@shah123: Those seem to be new modules - I noticed them on eBay the other day. What I can't see with these modules is the electrolytic capacitor that helps to smooth out the power supply for each module. It may be on the other side, but I don't see any through holes for it.

Without the additional capacitance, there could be problems when there are a few modules together (10 would seem like it may cause an issue). You could add the additional capacitors, of course.

Connections should be ok - it is the same way that the FC-16 modules connect to each other.

Someone else may want to comment if they have used these modules.
Arduino Libraries http://arduinocode.codeplex.com
Parola for Arduino http://parola.codeplex.com
Arduino++ blog https://arduinoplusplus.wordpress.com

lehighkid

My best guess is that if your limit with no external power is 6 then you may be getting power supply issues. Does it work better with 4 or 5 and/or have you tried additional power?

I don't have any experience with nodemcu. I am surprised if PROGMEM does not work, but without knowing much about it I don't even want to guess.
Marco - thanks for the suggestion - I haven't gone back to the mega since getting it up and running on the nodemcu which ironically does not have the same issues while either connected via usb or directly to vin.  Will have to go back and test when I get more free time. 

As for the nodemcu there was one additional error that I had to encounter and that was the definition of CLOSING in the animation header that conflicted with the esp8622wifi library.  I omitted that in the header file and avoided the closing animation and all works perfectly.  It is now hooked up to MQTT with a message queue where I can add, update, delete messages all with individual animations and properties controlled remotely via wifi and text.

The code is lengthy and unoptimized ATM and it is only with 6 displays but it is a prototype to build a much larger scrolling display.  I will try to share the code once it is cleaned up and happy to share some insights/learning experiences with anyone interested in the interim.

Thanks again for such great and well documented libraries - it made it very easy!

The_Undertaker

#829
Apr 19, 2016, 09:16 am Last Edit: Apr 19, 2016, 09:23 am by The_Undertaker
You use one of the tools provided or you can do your own.

There is a Microsoft Excel spreadsheet with a macro that provides a graphical interface to turn dots on and off. It will then produce the text for the font definition that you can cut and paste. The first worksheet of the workbook has instructions.

These tools are in the FontBuilder folder of MD_MAX72xx and also described in the latest html documentation. You may need to download version 2.8 from the site to get the latest tools.
Thanxx... marco_c now I can build some coustom Chars...using d font builder..
Video here:- https://www.youtube.com/watch?v=7FCfc45WLyY
I got a code from here:- http://forum.arduino.cc/index.php?topic=349553.0
cos am a very beginner I edited the Font data.h and could some how manage
to animate some custom characters... it was a two row code... having zone 0 n zone 1
can u help me to remove d zone n create a neat code having no zones cos I only have 5 dot matrix displays.. Have attached d edited code below


Thanxx in advance  

marco_c

#830
Apr 19, 2016, 11:34 am Last Edit: Apr 19, 2016, 11:35 am by marco_c
Not sure why you started from that code. There are a number of examples with the Parola library that you can use. For example, the one with Japanese and Arabic characters.

Sorry but I do not have time to edit other people's code.
Arduino Libraries http://arduinocode.codeplex.com
Parola for Arduino http://parola.codeplex.com
Arduino++ blog https://arduinoplusplus.wordpress.com

lehighkid

My best guess is that if your limit with no external power is 6 then you may be getting power supply issues. Does it work better with 4 or 5 and/or have you tried additional power?

I don't have any experience with nodemcu. I am surprised if PROGMEM does not work, but without knowing much about it I don't even want to guess.
So after some time using the nodemcu artifacts do come up too - same issue.  I have tried with a few less and I have also tried inserting direct power both at the start and the middle as well as powering half from the nodemcu and half with direct power and in all cases it is about 10-15 minutes of continuous scrolling then artifacts appear and require a reset to unstick the pixels.  

I've tried everything I can think of (or know of and that isn't much) to get isolated power to them.  I don't know if it is the hardware or not but I plan on building a bigger one so I have ordered the parola kits from electrodragon and will try luck with them.  

Will come back on any changes or the next go around.

rgm

I made some pleasing custom shapes, two hearts and two cats.  I'll just leave them here in expanded binary form so they're easier to tweak if you like.
Code: [Select]

uint8_t heart1[] = {9,
 0b00001110,
 0b00011111,
 0b00111111,
 0b01111111,
 0b11111110,
 0b01111111,
 0b00111111,
 0b00011111,
 0b00001110
};

uint8_t heart2[] = {7,
 0b00001110,
 0b00011111,
 0b00111111,
 0b01111110,
 0b00111111,
 0b00011111,
 0b00001110
};

uint8_t cat1[] = { 11,
  0b00001110,
  0b11011011,
  0b10110110,
  0b00111010,
  0b11111111,
  0b00111000,
  0b01111000,
  0b10111000,
  0b11111000,
  0b00001101,
  0b00000110
};

uint8_t cat2[] = { 9,
  0b00011111,
  0b01111110,
  0b11100100,
  0b11111100,
  0b10111100,
  0b11111100,
  0b11100100,
  0b01111110,
  0b00011111
};

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