20.4.2.5.1 DMX Transmit

The following procedure is used for DMX transmit:

1. Configure the clock input and baud rate as detailed in Clocking and Baud Rate Configuration for 250 kbaud.
2. Configure DMX mode by writing ‘0b1010’ to the MODE[3:0] bits.
3. Set STP to ‘0b10’.
4. Configure the TX interrupt watermark using the TXWM[2:0] bits.
5. Write to Parameter 1 equal to the number of bytes – 1 (not including start code).
6. Set the ON and TXEN bits.
7. Write the start code value to UxTXB.

Writing the start code to UxTXB will transmit a 25-bit Break, MAB and start code.

1. Write slot data bytes to UxTXB.

If not all bytes defined by Parameter 1 are written, the line will return to the Idle state. Once all bytes are written, the frame is considered complete and the next write to UxTXB will send a Break for the next frame.