Tetsuro Tatsuoka
/
BH1792GLC_Eval
Measuring plethysmogram with BH1792GLC (Rohm Semiconductor) and calculating pulse rate
PulseRate.cpp@1:90f70c146a26, 2018-02-05 (annotated)
- Committer:
- t_tatsuoka
- Date:
- Mon Feb 05 21:28:19 2018 +0000
- Revision:
- 1:90f70c146a26
- Parent:
- 0:18d735a66926
Ver. 1.0.1 ???beep?????????????????????????
Who changed what in which revision?
User | Revision | Line number | New contents of line |
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t_tatsuoka | 0:18d735a66926 | 1 | /** |
t_tatsuoka | 0:18d735a66926 | 2 | * @file PulseRate.cpp |
t_tatsuoka | 0:18d735a66926 | 3 | * @brief Measuring plethysmogram and calc pulse rate |
t_tatsuoka | 1:90f70c146a26 | 4 | * @date 2018.02.06 |
t_tatsuoka | 1:90f70c146a26 | 5 | * @version 1.1.1 |
t_tatsuoka | 0:18d735a66926 | 6 | */ |
t_tatsuoka | 0:18d735a66926 | 7 | #include "PulseRate.h" |
t_tatsuoka | 0:18d735a66926 | 8 | |
t_tatsuoka | 0:18d735a66926 | 9 | #ifdef _OP_MODE_INT_AD |
t_tatsuoka | 0:18d735a66926 | 10 | /** Constructor |
t_tatsuoka | 0:18d735a66926 | 11 | * @param sensor Pin for A/D converter |
t_tatsuoka | 0:18d735a66926 | 12 | * @param sync_led Pin for synchronous LED |
t_tatsuoka | 0:18d735a66926 | 13 | * @param beep Pin for piezo sounder |
t_tatsuoka | 0:18d735a66926 | 14 | */ |
t_tatsuoka | 0:18d735a66926 | 15 | PulseRate::PulseRate(PinName sensor, PinName sync_led, PinName beep) : |
t_tatsuoka | 0:18d735a66926 | 16 | _sensor(sensor), _sync_led(sync_led), _beep(beep) |
t_tatsuoka | 0:18d735a66926 | 17 | { |
t_tatsuoka | 0:18d735a66926 | 18 | init(); |
t_tatsuoka | 0:18d735a66926 | 19 | } |
t_tatsuoka | 0:18d735a66926 | 20 | #elif defined _OP_MODE_BH1792GLC |
t_tatsuoka | 0:18d735a66926 | 21 | /** Constructor |
t_tatsuoka | 0:18d735a66926 | 22 | * @param bh_sda Pin for SDA on BH1792GLC |
t_tatsuoka | 0:18d735a66926 | 23 | * @param bh_scl Pin for SCL on BH1792GLC |
t_tatsuoka | 0:18d735a66926 | 24 | * @param bh_int Pin for INT on BH1792GLC |
t_tatsuoka | 0:18d735a66926 | 25 | * @param sync_led Pin for synchronous LED |
t_tatsuoka | 0:18d735a66926 | 26 | * @param beep Pin for piezo sounder |
t_tatsuoka | 0:18d735a66926 | 27 | */ |
t_tatsuoka | 0:18d735a66926 | 28 | PulseRate::PulseRate(PinName bh_sda, PinName bh_scl, PinName bh_int, PinName sync_led, PinName beep) : |
t_tatsuoka | 0:18d735a66926 | 29 | _bh(bh_sda, bh_scl, bh_int), _sync_led(sync_led), _beep(beep) |
t_tatsuoka | 0:18d735a66926 | 30 | { |
t_tatsuoka | 0:18d735a66926 | 31 | init(); |
t_tatsuoka | 0:18d735a66926 | 32 | } |
t_tatsuoka | 0:18d735a66926 | 33 | #endif |
t_tatsuoka | 0:18d735a66926 | 34 | |
t_tatsuoka | 0:18d735a66926 | 35 | /** Initialize |
t_tatsuoka | 0:18d735a66926 | 36 | */ |
t_tatsuoka | 0:18d735a66926 | 37 | void PulseRate::init() |
t_tatsuoka | 0:18d735a66926 | 38 | { |
t_tatsuoka | 0:18d735a66926 | 39 | _sync_led = LED_OFF; |
t_tatsuoka | 0:18d735a66926 | 40 | _val = 0; |
t_tatsuoka | 0:18d735a66926 | 41 | _wave_flag = false; |
t_tatsuoka | 0:18d735a66926 | 42 | _pr_flag = false; |
t_tatsuoka | 1:90f70c146a26 | 43 | _sync_flag = false; |
t_tatsuoka | 0:18d735a66926 | 44 | _sampling_num = 0; |
t_tatsuoka | 0:18d735a66926 | 45 | _mv_idx = 0; |
t_tatsuoka | 0:18d735a66926 | 46 | _beep.period(1.0/BEEP_FREQ); |
t_tatsuoka | 0:18d735a66926 | 47 | } |
t_tatsuoka | 0:18d735a66926 | 48 | |
t_tatsuoka | 0:18d735a66926 | 49 | /** Start interval timer |
t_tatsuoka | 0:18d735a66926 | 50 | */ |
t_tatsuoka | 0:18d735a66926 | 51 | void PulseRate::start_sampling() |
t_tatsuoka | 0:18d735a66926 | 52 | { |
t_tatsuoka | 0:18d735a66926 | 53 | _sampling.attach(callback(this, &PulseRate::interval_timer), SAMPLING_RATE); |
t_tatsuoka | 0:18d735a66926 | 54 | } |
t_tatsuoka | 0:18d735a66926 | 55 | |
t_tatsuoka | 0:18d735a66926 | 56 | /** Get waveform data |
t_tatsuoka | 0:18d735a66926 | 57 | * @param &num Sampling number |
t_tatsuoka | 0:18d735a66926 | 58 | * @param &wave_val Waveform value |
t_tatsuoka | 0:18d735a66926 | 59 | * @retval true Ready for data |
t_tatsuoka | 0:18d735a66926 | 60 | * @retval false Not ready |
t_tatsuoka | 0:18d735a66926 | 61 | */ |
t_tatsuoka | 0:18d735a66926 | 62 | bool PulseRate::get_wave(uint32_t &num, int32_t &wave_val) |
t_tatsuoka | 0:18d735a66926 | 63 | { |
t_tatsuoka | 0:18d735a66926 | 64 | if(_wave_flag) { |
t_tatsuoka | 0:18d735a66926 | 65 | _wave_flag = false; |
t_tatsuoka | 0:18d735a66926 | 66 | num = _sampling_num; |
t_tatsuoka | 0:18d735a66926 | 67 | wave_val = _val; |
t_tatsuoka | 0:18d735a66926 | 68 | return true; |
t_tatsuoka | 0:18d735a66926 | 69 | } else { |
t_tatsuoka | 0:18d735a66926 | 70 | return false; |
t_tatsuoka | 0:18d735a66926 | 71 | } |
t_tatsuoka | 0:18d735a66926 | 72 | } |
t_tatsuoka | 0:18d735a66926 | 73 | |
t_tatsuoka | 0:18d735a66926 | 74 | /** Gat pulse rate |
t_tatsuoka | 0:18d735a66926 | 75 | * @param &pr Pulse rate |
t_tatsuoka | 0:18d735a66926 | 76 | * @retval true Ready for data |
t_tatsuoka | 0:18d735a66926 | 77 | * @retval false Not ready |
t_tatsuoka | 0:18d735a66926 | 78 | */ |
t_tatsuoka | 0:18d735a66926 | 79 | bool PulseRate::get_pr_val(uint32_t &pr) |
t_tatsuoka | 0:18d735a66926 | 80 | { |
t_tatsuoka | 0:18d735a66926 | 81 | if(_pr_flag) { |
t_tatsuoka | 0:18d735a66926 | 82 | _pr_flag = false; |
t_tatsuoka | 0:18d735a66926 | 83 | pr = _pr; |
t_tatsuoka | 0:18d735a66926 | 84 | return true; |
t_tatsuoka | 0:18d735a66926 | 85 | } else { |
t_tatsuoka | 0:18d735a66926 | 86 | return false; |
t_tatsuoka | 0:18d735a66926 | 87 | } |
t_tatsuoka | 0:18d735a66926 | 88 | } |
t_tatsuoka | 0:18d735a66926 | 89 | |
t_tatsuoka | 0:18d735a66926 | 90 | /** Interval timer |
t_tatsuoka | 0:18d735a66926 | 91 | */ |
t_tatsuoka | 0:18d735a66926 | 92 | void PulseRate::interval_timer() |
t_tatsuoka | 0:18d735a66926 | 93 | { |
t_tatsuoka | 0:18d735a66926 | 94 | |
t_tatsuoka | 0:18d735a66926 | 95 | /* Pulse waveform */ |
t_tatsuoka | 0:18d735a66926 | 96 | #ifdef _OP_MODE_INT_AD |
t_tatsuoka | 0:18d735a66926 | 97 | _val = ((int32_t)(_sensor.read_u16()) - AD_OFFSET); /* Get AD value */ |
t_tatsuoka | 0:18d735a66926 | 98 | #elif defined _OP_MODE_BH1792GLC |
t_tatsuoka | 0:18d735a66926 | 99 | if(_bh.get_val(_val)) { |
t_tatsuoka | 0:18d735a66926 | 100 | //printf("Value is set 0.\r\n"); |
t_tatsuoka | 0:18d735a66926 | 101 | _val = 0; |
t_tatsuoka | 0:18d735a66926 | 102 | } |
t_tatsuoka | 0:18d735a66926 | 103 | _val = -_val; |
t_tatsuoka | 0:18d735a66926 | 104 | #endif |
t_tatsuoka | 0:18d735a66926 | 105 | |
t_tatsuoka | 0:18d735a66926 | 106 | _val = hpf(_val); /* High pass filter (Comment out if not necessary) */ |
t_tatsuoka | 0:18d735a66926 | 107 | _sampling_num = (_sampling_num + 1) % SPL_NUM; /* Update sampling number */ |
t_tatsuoka | 0:18d735a66926 | 108 | _wave_flag = true; /* Set ready flag for pulse waveform */ |
t_tatsuoka | 0:18d735a66926 | 109 | |
t_tatsuoka | 0:18d735a66926 | 110 | /* Pulse rate */ |
t_tatsuoka | 0:18d735a66926 | 111 | if(detect_peak(_val)) { /* If detecting pulse */ |
t_tatsuoka | 0:18d735a66926 | 112 | calc_pr(); /* Calculate pulse rate including flag set */ |
t_tatsuoka | 0:18d735a66926 | 113 | } |
t_tatsuoka | 0:18d735a66926 | 114 | |
t_tatsuoka | 0:18d735a66926 | 115 | /* Control LED and Beep */ |
t_tatsuoka | 1:90f70c146a26 | 116 | if(_sync_flag) { |
t_tatsuoka | 1:90f70c146a26 | 117 | _sync_flag = false; |
t_tatsuoka | 0:18d735a66926 | 118 | _sync_led = LED_ON; |
t_tatsuoka | 0:18d735a66926 | 119 | _beep.write(BEEP_LOUD); |
t_tatsuoka | 0:18d735a66926 | 120 | } else { |
t_tatsuoka | 0:18d735a66926 | 121 | _sync_led = LED_OFF; |
t_tatsuoka | 0:18d735a66926 | 122 | _beep.write(0); |
t_tatsuoka | 0:18d735a66926 | 123 | } |
t_tatsuoka | 0:18d735a66926 | 124 | } |
t_tatsuoka | 0:18d735a66926 | 125 | |
t_tatsuoka | 0:18d735a66926 | 126 | /** Fixed point high pass filter |
t_tatsuoka | 0:18d735a66926 | 127 | * @param val Input value |
t_tatsuoka | 0:18d735a66926 | 128 | * @return Output value |
t_tatsuoka | 0:18d735a66926 | 129 | * |
t_tatsuoka | 0:18d735a66926 | 130 | * A/D value of mbed is Q6 format. |
t_tatsuoka | 0:18d735a66926 | 131 | * Please shift in advance if necessary. |
t_tatsuoka | 0:18d735a66926 | 132 | */ |
t_tatsuoka | 0:18d735a66926 | 133 | int32_t PulseRate::hpf(int32_t val) |
t_tatsuoka | 0:18d735a66926 | 134 | { |
t_tatsuoka | 0:18d735a66926 | 135 | int32_t reg, ret_val; |
t_tatsuoka | 0:18d735a66926 | 136 | int64_t temp_val; |
t_tatsuoka | 0:18d735a66926 | 137 | |
t_tatsuoka | 0:18d735a66926 | 138 | temp_val = (int64_t)COEF_AH * (int64_t)_reg_hpf; |
t_tatsuoka | 0:18d735a66926 | 139 | reg = val + (int32_t)(temp_val >> 30); |
t_tatsuoka | 0:18d735a66926 | 140 | ret_val = reg - _reg_hpf; |
t_tatsuoka | 0:18d735a66926 | 141 | temp_val = (int64_t)COEF_BH * (int64_t)ret_val; |
t_tatsuoka | 0:18d735a66926 | 142 | ret_val = (int32_t)(temp_val >> 30); |
t_tatsuoka | 0:18d735a66926 | 143 | _reg_hpf = reg; |
t_tatsuoka | 0:18d735a66926 | 144 | return ret_val; |
t_tatsuoka | 0:18d735a66926 | 145 | } |
t_tatsuoka | 0:18d735a66926 | 146 | |
t_tatsuoka | 0:18d735a66926 | 147 | /** Detect pulse peak |
t_tatsuoka | 0:18d735a66926 | 148 | * @param &val Waveform data value |
t_tatsuoka | 0:18d735a66926 | 149 | * @retval true Detected pulse peak |
t_tatsuoka | 0:18d735a66926 | 150 | * @retval false No detection |
t_tatsuoka | 0:18d735a66926 | 151 | */ |
t_tatsuoka | 0:18d735a66926 | 152 | bool PulseRate::detect_peak(int32_t val) |
t_tatsuoka | 0:18d735a66926 | 153 | { |
t_tatsuoka | 0:18d735a66926 | 154 | int i; |
t_tatsuoka | 0:18d735a66926 | 155 | bool retVal = false; |
t_tatsuoka | 0:18d735a66926 | 156 | |
t_tatsuoka | 0:18d735a66926 | 157 | /* Calculate differential of input value */ |
t_tatsuoka | 0:18d735a66926 | 158 | _mv_buf[_mv_idx] = val - _prev_val; |
t_tatsuoka | 0:18d735a66926 | 159 | _prev_val = val; |
t_tatsuoka | 0:18d735a66926 | 160 | _mv_idx = (_mv_idx + 1) % MV_LENGTH; |
t_tatsuoka | 0:18d735a66926 | 161 | |
t_tatsuoka | 0:18d735a66926 | 162 | /* Calculate moving averaging */ |
t_tatsuoka | 0:18d735a66926 | 163 | _detect_val = 0; |
t_tatsuoka | 0:18d735a66926 | 164 | for(i=0; i<MV_LENGTH; i++) { |
t_tatsuoka | 0:18d735a66926 | 165 | _detect_val += _mv_buf[i]; |
t_tatsuoka | 0:18d735a66926 | 166 | } |
t_tatsuoka | 0:18d735a66926 | 167 | _detect_val = _detect_val / MV_LENGTH; |
t_tatsuoka | 0:18d735a66926 | 168 | |
t_tatsuoka | 0:18d735a66926 | 169 | /* Calculate exponential decline for threshold line */ |
t_tatsuoka | 0:18d735a66926 | 170 | _threshold_val = (int32_t)((double)_prev_th_val * TH_COEF); |
t_tatsuoka | 0:18d735a66926 | 171 | |
t_tatsuoka | 0:18d735a66926 | 172 | if(_detect_val >= _threshold_val) { |
t_tatsuoka | 0:18d735a66926 | 173 | /* If exceeding threshold */ |
t_tatsuoka | 0:18d735a66926 | 174 | if(_prev_dt_val < _prev_th_val) { |
t_tatsuoka | 0:18d735a66926 | 175 | /* If previous value is under threshold and over ignore value */ |
t_tatsuoka | 0:18d735a66926 | 176 | if((_detect_val > PEAK_MIN) && (_pr_counter >= PR_INT_MIN)) { |
t_tatsuoka | 0:18d735a66926 | 177 | /* Detecting peak!!! */ |
t_tatsuoka | 0:18d735a66926 | 178 | retVal = true; |
t_tatsuoka | 0:18d735a66926 | 179 | } |
t_tatsuoka | 0:18d735a66926 | 180 | } |
t_tatsuoka | 0:18d735a66926 | 181 | /* Previous threshold value is set to input value */ |
t_tatsuoka | 0:18d735a66926 | 182 | _prev_th_val = _detect_val; |
t_tatsuoka | 0:18d735a66926 | 183 | } else { |
t_tatsuoka | 0:18d735a66926 | 184 | /* Previous threshold value is set to decline value */ |
t_tatsuoka | 0:18d735a66926 | 185 | _prev_th_val = _threshold_val; |
t_tatsuoka | 0:18d735a66926 | 186 | } |
t_tatsuoka | 0:18d735a66926 | 187 | /* Update previous input value */ |
t_tatsuoka | 0:18d735a66926 | 188 | _prev_dt_val = _detect_val; |
t_tatsuoka | 0:18d735a66926 | 189 | |
t_tatsuoka | 0:18d735a66926 | 190 | /* Increment pulse rate counter */ |
t_tatsuoka | 0:18d735a66926 | 191 | _pr_counter++; |
t_tatsuoka | 0:18d735a66926 | 192 | |
t_tatsuoka | 0:18d735a66926 | 193 | return retVal; |
t_tatsuoka | 0:18d735a66926 | 194 | } |
t_tatsuoka | 0:18d735a66926 | 195 | |
t_tatsuoka | 0:18d735a66926 | 196 | /** Calculate pulse rate |
t_tatsuoka | 0:18d735a66926 | 197 | */ |
t_tatsuoka | 0:18d735a66926 | 198 | void PulseRate::calc_pr() |
t_tatsuoka | 0:18d735a66926 | 199 | { |
t_tatsuoka | 0:18d735a66926 | 200 | int i; |
t_tatsuoka | 0:18d735a66926 | 201 | |
t_tatsuoka | 0:18d735a66926 | 202 | /* If pulse rate counter is within maximum value */ |
t_tatsuoka | 0:18d735a66926 | 203 | if(_pr_counter <= PR_INT_MAX) { |
t_tatsuoka | 0:18d735a66926 | 204 | /* Calculate moving averaging */ |
t_tatsuoka | 0:18d735a66926 | 205 | _pr_buf[_pr_idx] = _pr_counter; |
t_tatsuoka | 0:18d735a66926 | 206 | _pr_idx = (_pr_idx + 1) % PR_LENGTH; |
t_tatsuoka | 0:18d735a66926 | 207 | _pr = 0; |
t_tatsuoka | 0:18d735a66926 | 208 | for(i=0; i<PR_LENGTH; i++) { |
t_tatsuoka | 0:18d735a66926 | 209 | _pr += _pr_buf[i]; |
t_tatsuoka | 0:18d735a66926 | 210 | } |
t_tatsuoka | 0:18d735a66926 | 211 | /* Set pulse rate value */ |
t_tatsuoka | 0:18d735a66926 | 212 | _pr = PR_1MIN_SPL * PR_LENGTH / _pr; |
t_tatsuoka | 0:18d735a66926 | 213 | } else { |
t_tatsuoka | 0:18d735a66926 | 214 | /* Pulse rate is set to invalid value */ |
t_tatsuoka | 0:18d735a66926 | 215 | _pr = 0; |
t_tatsuoka | 0:18d735a66926 | 216 | } |
t_tatsuoka | 0:18d735a66926 | 217 | _pr_counter = 0; |
t_tatsuoka | 0:18d735a66926 | 218 | |
t_tatsuoka | 0:18d735a66926 | 219 | /* Set pulse rate flag */ |
t_tatsuoka | 0:18d735a66926 | 220 | _pr_flag = true; |
t_tatsuoka | 1:90f70c146a26 | 221 | _sync_flag = true; |
t_tatsuoka | 0:18d735a66926 | 222 | } |