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wayoda / LedControl

An Arduino library for MAX7219 and MAX7221 Led display drivers
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image is mirrored on matrix #5

Closed sebulica closed 9 years ago

sebulica commented 9 years ago

i've tested your library on a max7219cgn controlled matrix 8x8.the "images" were mirrored on the matrix.for example "d" was "b".i've modified the library a little and now works like a charm :)

i've modified the spiTransfer from LedControl,bot setRow and setLed

i've added "7-row+1" to make it look normal

wayoda commented 9 years ago

This might have to do with a different wiring or even different mental conceptions about where column 0 is on a matrix.

Anyway, I wrote the library 4 years ago on nobody complained about this. So I'm not going to change the library code, because that would break all the code for every user of the library who has to recompile a project.

But thanks for the hint and I'm glad the code was useful for you.
Cheers Eberhard

marcelstoer commented 9 years ago

Same here...but I guess it really boils down to the question "where is led 0"? And what is a row and what is a column. If I run the sample sketch which displays "Arduino" I get the correct orientation. If the wires of the board point upwards, the characters are mirrored, though. Below image shows the start of the single() function which lights up every led one by one -> it started top right. This, however, is where it's supposed to start I believe.

max7219-where-is-0

tibfox commented 8 years ago

@sebulica thx for your solution. had the same problem ;) works like a charme !

of course big thanks @wayoda ;)