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Diffstat (limited to 'cores/arduino/wiring_pulse.c')
-rw-r--r--cores/arduino/wiring_pulse.c14
1 files changed, 8 insertions, 6 deletions
diff --git a/cores/arduino/wiring_pulse.c b/cores/arduino/wiring_pulse.c
index 3212f13..d6e0434 100644
--- a/cores/arduino/wiring_pulse.c
+++ b/cores/arduino/wiring_pulse.c
@@ -69,22 +69,24 @@ unsigned long pulseInLong(uint8_t pin, uint8_t state, unsigned long timeout)
uint8_t port = digitalPinToPort(pin);
uint8_t stateMask = (state ? bit : 0);
- unsigned long maxMicros = micros() + timeout;
+ unsigned long startMicros = micros();
// wait for any previous pulse to end
- while ((*portInputRegister(port) & bit) == stateMask)
- if (micros() > maxMicros)
+ while ((*portInputRegister(port) & bit) == stateMask) {
+ if (micros() - startMicros > timeout)
return 0;
+ }
// wait for the pulse to start
- while ((*portInputRegister(port) & bit) != stateMask)
- if (micros() > maxMicros)
+ while ((*portInputRegister(port) & bit) != stateMask) {
+ if (micros() - startMicros > timeout)
return 0;
+ }
unsigned long start = micros();
// wait for the pulse to stop
while ((*portInputRegister(port) & bit) == stateMask) {
- if (micros() > maxMicros)
+ if (micros() - startMicros > timeout)
return 0;
}
return micros() - start;