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#include <util/delay.h>

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// DMX

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// baud rate: 250k = 4µs / bit

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#define DMX_BAUD    (250 * 1000)

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#define DMX_US      4

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// CPU cycles / bit: 64 @ 16Mhz

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#define DMX_CYCLES  (F_CPU / DMX_BAUD)

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void dmx_init ()

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{

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    // dmx data out: idle (high)

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    sbi(&DMX_PORT, DMX_DATA);

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    sbi(&DMX_DDR, DMX_DATA);

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}

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static inline void dmx_high ()

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{

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    sbi(&DMX_PORT, DMX_DATA);

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}

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static inline void dmx_low ()

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{

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    cbi(&DMX_PORT, DMX_DATA);

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}

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#define dmx_pause(bits) _delay_us((DMX_US * bits))

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static void dmx_break ()

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{

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    // break

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    dmx_low();

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    dmx_pause(22);

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    // mark-after-break (MAB)

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    dmx_high();

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    dmx_pause(2);

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}

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#include "dmx_frame.c"

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static void dmx_packet (byte count, byte *out)

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{

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    dmx_break();

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    dmx_frame(0);

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    for (byte i = 0; i < count; i++) {

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        dmx_frame(out[i]);

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    }

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}