Vii Changing The Dmx Chipset - Intelligent USB-DMX interface Hardware Manual

Hardware
Pin 7 DMX – OUTPUT
Pin 8 3,3V or 5V
If
there is a correct signal on pins 7 and 8 but nothing on the XLR
connector, please check the 4 resistors (see the XLR chapter).
if there is not signal on pin 4, the interface has another problem.
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VII Changing the DMX chipset