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#ifndef QMSK_SWITCH_H

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#define QMSK_SWITCH_H

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#include "stdlib.h"

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extern byte switch_mask;

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/*

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 * Setup switch input triggering on SWITCH_DDR/PORT/PIN using SWITCH_PCMSK/PCIE/PCIF interrupts.

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 */

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void switch_init (void)

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{

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    switch_mask = SWITCH_MASK;

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    // input mode

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    byte bit = 1;

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    for (byte i = 0; i < 8; i++) {

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        if (SWITCH_MASK & bit) {

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            cbi(SWITCH_DDR, i);

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            // pull-up

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            sbi(SWITCH_PORT, i);

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        }

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        bit <<= 1;

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    }

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    // interrupt mask for port

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    *SWITCH_PCMSK = SWITCH_MASK;

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    // enable interrupts

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    sbi(&PCICR, SWITCH_PCIE);

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}

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/*

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 * Update switch state if changed.

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 *

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 * Returns 1 if changed, 0 if no changes.

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 *

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 * TODO: debouncing

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 */

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byte switch_read (byte *sp);

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#endif