Chris Taylor / SignalCapture

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DigitalPinCapture.h@0:c6f86d422a7e, 2014-09-27 (annotated)

Committer:
taylorza
Date:
Sat Sep 27 04:04:16 2014 +0000
Revision:
0:c6f86d422a7e
Initial commit of the Signal Capture library

Who changed what in which revision?

UserRevisionLine numberNew contents of line
taylorza 0:c6f86d422a7e 1 ///////////////////////////////////////////////////////////////////////////////
taylorza 0:c6f86d422a7e 2 // Signal Capture Library
taylorza 0:c6f86d422a7e 3 // Author: Chris Taylor (taylorza)
taylorza 0:c6f86d422a7e 4 #ifndef __DIGITALPINCAPTURE_H__
taylorza 0:c6f86d422a7e 5 #define __DIGITALPINCAPTURE_H__
taylorza 0:c6f86d422a7e 6
taylorza 0:c6f86d422a7e 7 /** Captures the digital wave form of a pin into a timing buffer. */
taylorza 0:c6f86d422a7e 8 class DigitalPinCapture
taylorza 0:c6f86d422a7e 9 {
taylorza 0:c6f86d422a7e 10 public:
taylorza 0:c6f86d422a7e 11 /** Create an instance of DigitalPinCapture connected to the specified pin
taylorza 0:c6f86d422a7e 12 * @note The DigitalPinCapture class polls the state of the pin and therefore might be less accurate than
taylorza 0:c6f86d422a7e 13 * using InterruptPinCapture. However, it has the advantage that it does not require an interrupt capable pin.
taylorza 0:c6f86d422a7e 14 */
taylorza 0:c6f86d422a7e 15 DigitalPinCapture(PinName pin, PinMode mode);
taylorza 0:c6f86d422a7e 16
taylorza 0:c6f86d422a7e 17 /** Maximum time to wait for waveform data to arrive or completely fill the timing buffer.
taylorza 0:c6f86d422a7e 18 * @param us Timeout specified in microseconds
taylorza 0:c6f86d422a7e 19 */
taylorza 0:c6f86d422a7e 20 void setReadTimeout(uint32_t us);
taylorza 0:c6f86d422a7e 21
taylorza 0:c6f86d422a7e 22 /** Waits for the pin to transition to the trigger state and proceeds to capture the
taylorza 0:c6f86d422a7e 23 * pins transition timing into the timing buffer.
taylorza 0:c6f86d422a7e 24 * @param triggerState State that the pin must transistion to before the readings are captured
taylorza 0:c6f86d422a7e 25 * @param pReadings Pointer to the timing buffer that will contain the readings in microseconds
taylorza 0:c6f86d422a7e 26 * @param count The maximum number of readings that can be held in the buffer
taylorza 0:c6f86d422a7e 27 * @returns The number of timings captured in the buffer.
taylorza 0:c6f86d422a7e 28 */
taylorza 0:c6f86d422a7e 29 int read(bool triggerState, uint32_t *pReadings, int count);
taylorza 0:c6f86d422a7e 30
taylorza 0:c6f86d422a7e 31 /** Immediately start capturing the pin transition timing into the timing buffer.
taylorza 0:c6f86d422a7e 32 * @param pInitialState Pointer to a bool that will have the initial state of the pin at the time the capture started.
taylorza 0:c6f86d422a7e 33 * @param pReadings Pointer to the timing buffer that will contain the readings in microseconds
taylorza 0:c6f86d422a7e 34 * @param count The maximum number of readings that can be held in the buffer
taylorza 0:c6f86d422a7e 35 * @returns The number of timings captured in the buffer.
taylorza 0:c6f86d422a7e 36 */
taylorza 0:c6f86d422a7e 37 int read(bool *pInitialState, uint32_t *pReadings, int count);
taylorza 0:c6f86d422a7e 38
taylorza 0:c6f86d422a7e 39 private:
taylorza 0:c6f86d422a7e 40 int readInternal(bool *pPinState, uint32_t *pReadings, int count, bool waitForTrigger);
taylorza 0:c6f86d422a7e 41
taylorza 0:c6f86d422a7e 42 private:
taylorza 0:c6f86d422a7e 43 DigitalIn _signalPin;
taylorza 0:c6f86d422a7e 44 uint32_t _readTimeout;
taylorza 0:c6f86d422a7e 45 };
taylorza 0:c6f86d422a7e 46 #endif //__DIGITALPINCAPTURE_H__