pulseInLong: fix incorrect timeout handling
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@ -69,25 +69,22 @@ unsigned long pulseInLong(uint8_t pin, uint8_t state, unsigned long timeout)
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uint8_t port = digitalPinToPort(pin);
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uint8_t stateMask = (state ? bit : 0);
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// convert the timeout from microseconds to a number of times through
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// the initial loop; it takes 16 clock cycles per iteration.
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unsigned long numloops = 0;
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unsigned long maxloops = microsecondsToClockCycles(timeout);
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unsigned long maxMicros = micros() + timeout;
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// wait for any previous pulse to end
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while ((*portInputRegister(port) & bit) == stateMask)
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if (numloops++ == maxloops)
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if (micros() > maxMicros)
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return 0;
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// wait for the pulse to start
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while ((*portInputRegister(port) & bit) != stateMask)
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if (numloops++ == maxloops)
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if (micros() > maxMicros)
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return 0;
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unsigned long start = micros();
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// wait for the pulse to stop
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while ((*portInputRegister(port) & bit) == stateMask) {
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if (numloops++ == maxloops)
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if (micros() > maxMicros)
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return 0;
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}
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return micros() - start;
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