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Topic: LED matrix display - MD_Parola, MD_MAX72xx and MD_MAXPanel (Read 559032 times) previous topic - next topic

Ryme_Extrinseca

Thank you.

I'll look into that too.

Just getting to grips with the library using the various methods to process my 22 led matrix display.

Many grateful thanks again.


M.

marco_c

Lots of examples to follow. IF you want to get more information you can look for all the articles with "Parola A to Z" on my blog site at the address in the post footer (link). There is also extensive documentation for MD_Parola and MD_MAX72xx in the docs subfolder of the relevant your library folder.
Arduino Libraries https://github.com/MajicDesigns?tab=Repositories
Parola for Arduino https://github.com/MajicDesigns/Parola
Arduino++ blog https://arduinoplusplus.wordpress.com

brunogerez

Hi! I'm new in this forum so I hope I'm doing this OK (I have already read the rules).

I got a question: How do I do to reduce the characters of the font lib?

In my program I only need a few characters such as "0, 1, 2, ..... 9, A, L, R, M, e, s, c". I've tried setting all the spaces in zero but it stills occupy memory.

I need to reduce the characters to have more free memory.

Thanks!!

marco_c

Quote
I need to reduce the characters to have more free memory.
To be clear, the memory you free up is flash memory, not RAM.

You can specify the start and end character for the font in the font definition. This works to reduce the majority of the unused characters. Read the documentation (docs folder) and look at the standard font definition as the example of what it looks like.

If you want to eliminate all the characters between the other characters then you can declare 'user characters'. Note that these will take up RAM instead of flash memory. There is an example sketch for this.

Arduino Libraries https://github.com/MajicDesigns?tab=Repositories
Parola for Arduino https://github.com/MajicDesigns/Parola
Arduino++ blog https://arduinoplusplus.wordpress.com

brunogerez


Ryme_Extrinseca

Hello,

I have always had success using the FC-16 modules with the Parola library. I can run 22 x FC-16 types in a string with no appreciable drop in performance. All very nice and reliable for project work. Thank you again Marco!

However, I invariably hit problems using the Generic-type modules.

On my latest attempt to implement a batch of the Generic-type (12 in a strip) I encounter a variation on their eccentricity.

I've 'hard wired' 12 Generic modules and fed them the 'Parola_Scrolling' example to test. The first sweep of the line of modules is fine with "Hello! Enter a new message?" scrolling fine. However, when the text attempts to scroll again the text is jumbled and has many artefacts left across various display modules.

If I reset the Uno board, the message will scroll successfully just once, then the whole thing returns artefacts and fairly good attempts at a comprehensive message is very hit and miss.

I decided to 'hard wire' the modules onto a veroboard as I was a little fed up of failed Dupont connections or connections popping off or out of sockets and poorly aligned modules for readability etc;

Much to my disappointment, this approach has also seemingly failed too, though it's a bit more stable in this later 'hardwired' approach.

Before I give up on the Generic module types, is there anything obvious I should be doing to the Generic modules themselves to ensure they work well as a collective set?

Thank you for your help.

M.

marco_c

How are you powering the modules? With that many modules you should be using an external power supply, not the Arduino +5V pin. It is possible that the generic modules have a different resistor that allows more current to the LED display and your power supply becomes insufficient.

Have you tried adding modules one at a time and seeing if there is a point at which the problems happen?

How are the modules wired? The only signal that needs to be module-to-module is the DATA IN to DATA OUT signals. All the rest can be wired in parallel. This will significantly improve the signal quality and power distribution.

Arduino Libraries https://github.com/MajicDesigns?tab=Repositories
Parola for Arduino https://github.com/MajicDesigns/Parola
Arduino++ blog https://arduinoplusplus.wordpress.com

Devaropi

Hello!

I have been struggling for a while in displaying any text effect besides the static printing. I have tried both, setting and not setting the zone with displayZoneText() and displayText(), but none of them will display text effects.

The static printing, for which I set zones, works just fine. But whenever I set the effect the LED goes off. The Parola_Animation_Catalog example script from the library will also work smoothly.

I have tried many things but I can't figure out what's the issue. Maybe you have any clue what's giving me trouble?

Thanks a lot in advance and congrats for such a nice work!


marco_c

Arduino Libraries https://github.com/MajicDesigns?tab=Repositories
Parola for Arduino https://github.com/MajicDesigns/Parola
Arduino++ blog https://arduinoplusplus.wordpress.com

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