| //***************************************************************************** |
| // |
| //! @file am_util_tap_detect.h |
| //! |
| //! @brief Tap Gesture Detector |
| //! |
| //! These functions implement the tap detector utility |
| // |
| //***************************************************************************** |
| |
| //***************************************************************************** |
| // |
| // Copyright (c) 2017, Ambiq Micro |
| // All rights reserved. |
| // |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are met: |
| // |
| // 1. Redistributions of source code must retain the above copyright notice, |
| // this list of conditions and the following disclaimer. |
| // |
| // 2. Redistributions in binary form must reproduce the above copyright |
| // notice, this list of conditions and the following disclaimer in the |
| // documentation and/or other materials provided with the distribution. |
| // |
| // 3. Neither the name of the copyright holder nor the names of its |
| // contributors may be used to endorse or promote products derived from this |
| // software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE |
| // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| // POSSIBILITY OF SUCH DAMAGE. |
| // |
| // This is part of revision v1.2.10-2-gea660ad-hotfix2 of the AmbiqSuite Development Package. |
| // |
| //***************************************************************************** |
| #ifndef AM_UTIL_TAP_DETECT_H |
| #define AM_UTIL_TAP_DETECT_H |
| |
| #ifdef __cplusplus |
| extern "C" |
| { |
| #endif |
| |
| |
| //***************************************************************************** |
| // |
| // Enumerated return constants |
| // |
| //***************************************************************************** |
| typedef enum |
| { |
| NO_TAP_DETECTED = 0, |
| TAP_OCCURED, // reports every tap |
| TAP_DETECTED, // only if a single tap is not part of double/triple |
| DOUBLE_TAP_DETECTED, |
| TRIPLE_TAP_DETECTED |
| }am_util_tap_detect_enum_t; |
| |
| |
| //***************************************************************************** |
| // |
| // Tap Detector Data Structure |
| // |
| //***************************************************************************** |
| typedef struct am_util_tap_detector |
| { |
| float accX; |
| float accY; |
| float accZ; |
| float prev_accX; |
| float prev_accY; |
| float prev_accZ; |
| float SlopeThreshold; |
| int previous_peak_location; |
| int current_sample; |
| int sample_count; |
| bool start_flag; |
| float sample_rate; |
| //in terms of seconds |
| float peak_min_width_seconds; |
| float group_peak_max_threshold_seconds; |
| //in terms of samples |
| int peak_min_width_samples; |
| int group_peak_max_threshold; |
| //record the max peak found so you can adjust threshold in future |
| float max_mag; |
| float mag; //magnitude of the partial derivatives |
| int dist; |
| //previous peak was double tap -> flag to sep[arate out double tap pairs |
| int previous_tap_was_dbl_tap; |
| |
| } am_util_tap_detect_t; |
| |
| //***************************************************************************** |
| // |
| // External function definitions |
| // |
| //***************************************************************************** |
| void am_util_tap_detect_init(am_util_tap_detect_t * tap, |
| float dp_min_seconds, |
| float dp_max_seconds, |
| float srate, |
| float slope_thresh); |
| void am_util_tap_detect_print(am_util_tap_detect_t * tap); |
| am_util_tap_detect_enum_t am_util_tap_detect_process_sample |
| (am_util_tap_detect_t * tap, |
| short accX, short accY, short accZ); |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif // AM_UTIL_TAP_DETECT_H |
| |
| |
