Reading DMX

["E.S. Rosenberg" <es.rosenberg+libftdi.i2net@xxxxxxxxx>]

Hi all,

Several years ago Rui Barreiros already posted a question on the subject which at the time doesn't seem to have been resolved and I am running into the same problem more or less:

The DMX packet is read but ends up shifted over different amounts of bit every read.

I currently suspect that this is all dependent on when the OS issues the ftdi_read_data() call, I suspect this because when I ran my test program using gdb the shifts were a lot more extreme (almost 0.5 packet) then when it was running directly.

The packet itself is basically:
1. BREAK (>= 88us of LOW)
2. MAB (>= 8us HIGH)
3. 25-513 data slots (1b start HIGH, 8b data, 2b STOP HIGH each)

So my question is: Is there any way to 'allign' the reads to the break+mab?

attached is my modified version of the serial_test.c example.

Side questions:

- Can someone on the list explain the different flow control options?

- What is the RTS?

Thanks,

Eliyahu - אליהו

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serial_test.c
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