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Published 20 hours ago • verified publisher icon csdexter

What PINs on arduino need to use?

Open itJunky opened this issue 8 years ago • 7 comments

Can't understand where i can find pins MOSI or SCK or SS on my arduino board =(

itJunky avatar Mar 26 '16 20:03 itJunky

https://www.arduino.cc/en/Reference/SPI Here i find it's 11,13,10 pins. But on my 16 srgments i see randomly moving. No one symbols =(

itJunky avatar Mar 26 '16 21:03 itJunky

Hello and thanks for opening this issue. 16- and 14- segment support is still experimental in this library. I did run some tests and I have yet to find a way to connect 2 MAX7219s to a 16/14-segment display so that what the code attempts to do actually works.

There are two main problems:

  1. the multiplex scan is not synchronized between the two chips (and this does not appear to be possible with the genuine MAX7219, but only with enhanced work-alikes such as the AS1106)
  2. extra circuitry is required to prevent one of the MAX7219s from sourcing the other one's sinks (which could be achieved with strategically placed diodes and/or with the MAX7221/AS1107 whose drivers are in Hi-Z mode when inactive)

As soon as I get some time to finish the tests, I'll be able to either come up with a solution or make it clear in the documentation that this setup doesn't work with the current chips.

I hope this explains the situation.

csdexter avatar Mar 26 '16 23:03 csdexter

I have this one http://www.dx.com/ru/p/produino-max7219-16-in-1-dot-matrix-display-control-module-for-arduino-white-black-422104#.VvaK5x8Vw3w Thanks for your work and fun for find a way ;)

itJunky avatar Mar 27 '16 12:03 itJunky

The link you posted is not for a 16-segment display, but rather a matrix. Matrices should work just fine -- and if they do not, that's a bug and I'm happy to debug and fix it with your help.

So, which one is it? 16-segment or matrix?

csdexter avatar Mar 27 '16 23:03 csdexter

May be matrix but it's from 16 separate 8x8 led blocks connected in series

itJunky avatar Mar 28 '16 07:03 itJunky

wow, it's library for X-segment displays... Before now i think and works only with 7-segments and doesn't know about another variants.

Now i need to control a matrix, not x-segment display.

itJunky avatar Mar 28 '16 13:03 itJunky

was this issue ever revisited? I'd love the features of this library. I was able to wire a 16-segment display as per the example, but I just get garbage. If i used the LedControl library and reference the segments like matrix coordinates, it works fine.

lain-d avatar Aug 27 '18 04:08 lain-d