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40
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1 |
* 250 kHz clock
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2 |
* 250000 bits / s
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3 |
* 4µs / bit
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4 |
* idle line = high (transmitter/master drives line high)
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5 |
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6 |
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7 |
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8 |
Packet structure:
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9 |
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10 |
* paket format
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11 |
* break
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12 |
* mark (MAB)
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13 |
* 2-512 frames
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14 |
* frame 0 = start code = 0x00
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15 |
* frame N = channel N = 0-255
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16 |
* 1 start bit, 8 data bits, 2 stop bits, no parity
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17 |
* mark (MTBF)
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18 |
* mark (MTAP)
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19 |
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20 |
* break
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21 |
* syncs start of DMX packet
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22 |
* >= 22 low bits (88 µs)
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23 |
* up to 1s
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24 |
* recommended 25 - 30 low bits
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25 |
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26 |
* mark after break (MAB)
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27 |
* immediately follows the break
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28 |
* high mark of > 2 bits (8µs)
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29 |
* up to 1s
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30 |
* recommended 3 high bits
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31 |
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32 |
* (channel frames)
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33 |
* first frame is start code (SC)
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34 |
* data value = 0x00 signifies dimmer data
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35 |
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36 |
* 11 bits / frame
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37 |
* 1 low bit (start bit)
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38 |
* 8 data bits (0-255)
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39 |
* 2 high bits (stop bits)
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40 |
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41 |
* mark time between frames (MTBF)
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42 |
* idle time between frames; line kept high
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43 |
* can be as short as desired
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44 |
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45 |
* between 1 and 512 sequential frames
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46 |
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47 |
* mark time between packets (MTBP)
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48 |
* after the last frame's stop bits
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49 |
* same as MTBF
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50 |
* idle time between packets; line kept high
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51 |
* can be as short as desired
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52 |
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53 |
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