Im working on an Arduino project that involves receiving DMX with a MAX485 chip. The pinout of the chip has the 2 dmx pins labeled as A and B, but all the DMX pinouts have them labeled as + and -. What connects to what? Looking around, I have seen diagrams showing both ways. Which one is correct?
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\$\begingroup\$ Do you have the DMX standard and MAX485 datasheet open to do comparison? The reason you see both is that RS485 chip manufacturers use two different conventions. Some name the inverting output A and some name the non-invertìng output A. DMX standard defines signal true (+) high being logic 1. \$\endgroup\$– JustmeCommented Jan 18, 2021 at 23:32
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MAX485 A is high when data is logic 1. DMX512 + is high when data is logic 1.
So MAX485 A pin is DMX data+.
