LxTeensy3DMX multiple universes over USB

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LxTeensy3DMX multiple universes over USB

Post by A_Lighting_Guy »

I am building a USB to DMX box with the LxTeensy3DMX library. One of the example sketches uses multiple universes with Artnet/sACN. Is there a way to adapt this code to work with a USB input?

Teensy 3.2
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Post by admin »

Yes, with Teensy it is possible to use DMX and USB at the same time. Teensy uses the regular Serial object to communicate via USB. LXTeensy3DMX_Library replaces Serial1,Serial2, and Serial3 with LXTeensyDMX, LXTeensyDMX1, and LXTeensyDMX2. For an overview of Teensy serial see https://www.pjrc.com/teensy/td_uart.html.

Practically, to get an acceptable DMX refresh rate you can't push the data for more than two universes through USB and out to DMX. One universe shouldn't be a problem. You can look at the DMXUSBSerial example in the LXUSARTDMX library (https://github.com/claudeheintz/LXUSARTDMX) for an example of how to do this for a Teensy2.

The problem with using a Teensy as a replacement for an ENTTEC DMXUSB Pro is that most software looks for the specific USB chip for the ENTTEC widget. A Teensy may or may not show up in the list of available devices or be found for a connection. This does not have anything to do with the serial connection working or not. It is a about how the software finds serial output connections.

LXConsole is permissive in this regard. It will attempt to communicate with any serial port it finds. The FTDI chip used by ENTTEC widgets has two possible drivers, D2XX and Virtual Com Port. The D2XX driver is superior for connecting to FTDI based devices. But, it is specific to FTDI chips. So, you must use a regular com port type connection to have LXConsole talk to a Teensy as if it was an ENTTEC widget.
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