Bob Giesberts / LDC1101

Library to communicate with LDC1101

Dependents:   Inductive_Sensor Inductive_Sensor_Jasper Inductive_Sensor_3

Fork of LDC1000 by First Last

LDC1101.cpp@21:7c9e04e7d34f, 2016-01-05 (annotated)

Committer:
bobgiesberts
Date:
Tue Jan 05 11:03:22 2016 +0000
Revision:
21:7c9e04e7d34f
Parent:
20:8e1b1efdbb49
Child:
22:8da965ce5af3
Fixed clock overflow (2^32 = 4294.96726 s = 71 min):;  - buffer added to count the times it overflows.; Fixed filename overwrite;  - file is created with a new name; Fixed sleep options;  - LDC in standby modus, SD card off

Who changed what in which revision?

UserRevisionLine numberNew contents of line
bobgiesberts 16:07d0e43c2d12 1 /**
bobgiesberts 16:07d0e43c2d12 2 * @file LDC1101.cpp
bobgiesberts 16:07d0e43c2d12 3 * @brief this C++ file contains all required
bobgiesberts 16:07d0e43c2d12 4 * functions to interface with Texas
bobgiesberts 16:07d0e43c2d12 5 * Instruments' LDC1101.
bobgiesberts 16:07d0e43c2d12 6 *
bobgiesberts 20:8e1b1efdbb49 7 * @author Victor Sluiter & Bob Giesberts
bobgiesberts 16:07d0e43c2d12 8 *
bobgiesberts 16:07d0e43c2d12 9 * @date 2015-12-09
bobgiesberts 16:07d0e43c2d12 10 */
bobgiesberts 16:07d0e43c2d12 11
bobgiesberts 16:07d0e43c2d12 12 #include "LDC1101.h"
bobgiesberts 16:07d0e43c2d12 13
bobgiesberts 16:07d0e43c2d12 14
bobgiesberts 18:fc9bb81a631f 15 LDC1101::LDC1101(PinName mosi, PinName miso, PinName sck, PinName cs, float capacitor, float f_CLKIN, PinName clock_out) : _spiport(mosi,miso,sck, NC), _cs_pin(cs)//, _clock(clock_out,1)
bobgiesberts 16:07d0e43c2d12 16 {
bobgiesberts 18:fc9bb81a631f 17 // settings
bobgiesberts 19:e205ab9142d8 18 _cap = capacitor;
bobgiesberts 16:07d0e43c2d12 19 _spiport.format(8,3);
bobgiesberts 16:07d0e43c2d12 20 _spiport.frequency(1E6);
bobgiesberts 18:fc9bb81a631f 21 setFrequency(f_CLKIN);
bobgiesberts 16:07d0e43c2d12 22
bobgiesberts 16:07d0e43c2d12 23 _cs_pin.write(1);
bobgiesberts 16:07d0e43c2d12 24 wait_us(100);
bobgiesberts 16:07d0e43c2d12 25
bobgiesberts 16:07d0e43c2d12 26 init();
bobgiesberts 16:07d0e43c2d12 27 }
bobgiesberts 16:07d0e43c2d12 28
bobgiesberts 21:7c9e04e7d34f 29 void LDC1101::func_mode(LDC_MODE mode) { writeSPI((uint8_t *)(&mode), 0x0B); wait_ms(0.8); }
bobgiesberts 21:7c9e04e7d34f 30 void LDC1101::sleep(void) { /* stop toggling the CLKIN pin input and drive the CLKIN pin Low */ func_mode( LDC_MODE_STANDBY ); }
bobgiesberts 21:7c9e04e7d34f 31 void LDC1101::wakeup(void) { /* start toggling the clock input on the CLKIN pin */ func_mode( LDC_MODE_ACTIVE ); wait(0.5); }
bobgiesberts 20:8e1b1efdbb49 32
bobgiesberts 20:8e1b1efdbb49 33
bobgiesberts 16:07d0e43c2d12 34 void LDC1101::init()
bobgiesberts 16:07d0e43c2d12 35 {
bobgiesberts 20:8e1b1efdbb49 36 /********* SETTINGS *****************
bobgiesberts 20:8e1b1efdbb49 37 ** C_sensor = 120 pF
bobgiesberts 20:8e1b1efdbb49 38 ** L_sensor = 5 uH
bobgiesberts 20:8e1b1efdbb49 39 ** Rs = ??? Ohm
bobgiesberts 20:8e1b1efdbb49 40 ** Rp_min = ??? Ohm
bobgiesberts 20:8e1b1efdbb49 41 **
bobgiesberts 20:8e1b1efdbb49 42 ** RCount = 65535
bobgiesberts 20:8e1b1efdbb49 43 ** Samplerate = 15.3 Hz
bobgiesberts 20:8e1b1efdbb49 44 ** t_conv = 65.5 ms
bobgiesberts 20:8e1b1efdbb49 45 **
bobgiesberts 20:8e1b1efdbb49 46 ** f_sensor_min = 6.4 MHz (d = inf)
bobgiesberts 20:8e1b1efdbb49 47 ** f_sensor_max = 10 MHz (d = 0)
bobgiesberts 20:8e1b1efdbb49 48 ** divider = (4*f_sensor_max)/f_CLKIN = 4*10/16 = 2,5 --> 2
bobgiesberts 20:8e1b1efdbb49 49 ************************************/
bobgiesberts 20:8e1b1efdbb49 50
bobgiesberts 20:8e1b1efdbb49 51
bobgiesberts 18:fc9bb81a631f 52 // Set LDC1101 in configuration modus
bobgiesberts 20:8e1b1efdbb49 53 func_mode( LDC_MODE_STANDBY ); // STANDBY = 0x01 naar 0x0B
bobgiesberts 18:fc9bb81a631f 54
bobgiesberts 20:8e1b1efdbb49 55 // - initialise LHR mode & enable SHUTDOWN mode
bobgiesberts 19:e205ab9142d8 56 setLHRmode();
bobgiesberts 16:07d0e43c2d12 57
bobgiesberts 19:e205ab9142d8 58 // - set ResponseTime to 6144
bobgiesberts 20:8e1b1efdbb49 59 setResponseTime( LDC_RESPONSE_6144 );
bobgiesberts 19:e205ab9142d8 60
bobgiesberts 20:8e1b1efdbb49 61 // - set Reference Count to highest resolution
bobgiesberts 20:8e1b1efdbb49 62 setReferenceCount( 0xffff );
bobgiesberts 20:8e1b1efdbb49 63
bobgiesberts 20:8e1b1efdbb49 64 // - set calibrated value for f_sensor_min (d = inf, no target)
bobgiesberts 20:8e1b1efdbb49 65 setf_sensorMin( 6.4 ); // 6.4 MHz
bobgiesberts 18:fc9bb81a631f 66
bobgiesberts 19:e205ab9142d8 67 // - disable RP_MAX
bobgiesberts 19:e205ab9142d8 68 // - set RP_MIN to 3 kOhm
bobgiesberts 20:8e1b1efdbb49 69 setRPsettings( 1, RPMIN_12 );
bobgiesberts 16:07d0e43c2d12 70
bobgiesberts 19:e205ab9142d8 71 // - set Divider to 2
bobgiesberts 20:8e1b1efdbb49 72 setDivider( DIVIDER_2 );
bobgiesberts 18:fc9bb81a631f 73
bobgiesberts 18:fc9bb81a631f 74 // Done configuring settings, set LDC1101 in measuring modus
bobgiesberts 20:8e1b1efdbb49 75 func_mode( LDC_MODE_ACTIVE );
bobgiesberts 16:07d0e43c2d12 76 }
bobgiesberts 16:07d0e43c2d12 77
bobgiesberts 20:8e1b1efdbb49 78 void LDC1101::setLHRmode( void ){
bobgiesberts 20:8e1b1efdbb49 79 writeSPIregister( 0x05, 0x03 ); // ALT_CONFIG: 0000 0011 --> LHR modus + Shutdown enabled
bobgiesberts 20:8e1b1efdbb49 80 writeSPIregister( 0x0C, 0x01 ); // D_CONFIG: Enables LHR modus, disables RP
bobgiesberts 19:e205ab9142d8 81 }
bobgiesberts 19:e205ab9142d8 82
bobgiesberts 19:e205ab9142d8 83 void LDC1101::setRPsettings(bool RP_MAX_DIS, RPMIN rpmin)
bobgiesberts 19:e205ab9142d8 84 {
bobgiesberts 19:e205ab9142d8 85 float rpmins[] = {96, 48, 24, 12, 6, 3, 1.5, 0.75};
bobgiesberts 19:e205ab9142d8 86 _RPmin = rpmins[rpmin];
bobgiesberts 19:e205ab9142d8 87 writeSPIregister(0x01, ((RP_MAX_DIS & 0x80) << 7 | rpmin));
bobgiesberts 19:e205ab9142d8 88 }
bobgiesberts 19:e205ab9142d8 89
bobgiesberts 17:a5cf2b4bec13 90 void LDC1101::setDivider(DIVIDER div)
bobgiesberts 17:a5cf2b4bec13 91 {
bobgiesberts 19:e205ab9142d8 92 uint8_t divs[] = {1, 2, 4, 8};
bobgiesberts 19:e205ab9142d8 93 _divider = divs[div];
bobgiesberts 17:a5cf2b4bec13 94 writeSPIregister(0x34, div);
bobgiesberts 20:8e1b1efdbb49 95 }
bobgiesberts 20:8e1b1efdbb49 96
bobgiesberts 20:8e1b1efdbb49 97 void LDC1101::setResponseTime(LDC_RESPONSE responsetime)
bobgiesberts 20:8e1b1efdbb49 98 {
bobgiesberts 20:8e1b1efdbb49 99 uint16_t resps[] = {0, 0, 192, 384, 768, 1536, 3072, 6144};
bobgiesberts 20:8e1b1efdbb49 100 _responsetime = resps[responsetime];
bobgiesberts 20:8e1b1efdbb49 101 uint8_t buffer[1];
bobgiesberts 20:8e1b1efdbb49 102 readSPI(buffer, 0x04, 1);
bobgiesberts 20:8e1b1efdbb49 103 writeSPIregister(0x04, (buffer[0] & 0xF8) + responsetime);
bobgiesberts 20:8e1b1efdbb49 104 }
bobgiesberts 20:8e1b1efdbb49 105
bobgiesberts 20:8e1b1efdbb49 106 void LDC1101::setReferenceCount(uint16_t rcount)
bobgiesberts 20:8e1b1efdbb49 107 {
bobgiesberts 20:8e1b1efdbb49 108 _Rcount = rcount;
bobgiesberts 20:8e1b1efdbb49 109 uint8_t LHR_RCOUNT_LSB = (rcount & 0x00ff);
bobgiesberts 20:8e1b1efdbb49 110 uint8_t LHR_RCOUNT_MSB = ((rcount & 0xff00) >> 8);
bobgiesberts 20:8e1b1efdbb49 111 writeSPIregister(0x30, LHR_RCOUNT_LSB); //LSB
bobgiesberts 20:8e1b1efdbb49 112 writeSPIregister(0x31, LHR_RCOUNT_MSB); //MSB
bobgiesberts 20:8e1b1efdbb49 113 }
bobgiesberts 20:8e1b1efdbb49 114
bobgiesberts 20:8e1b1efdbb49 115 void LDC1101::setSampleRate(float samplerate){ setReferenceCount( ((_fCLKIN/samplerate)-55)/16 ); }
bobgiesberts 17:a5cf2b4bec13 116
bobgiesberts 17:a5cf2b4bec13 117
bobgiesberts 20:8e1b1efdbb49 118 void LDC1101::setf_sensorMin(float f_sensor_min)
bobgiesberts 16:07d0e43c2d12 119 {
bobgiesberts 20:8e1b1efdbb49 120 uint8_t buffer[1];
bobgiesberts 20:8e1b1efdbb49 121 readSPI(buffer, 0x04, 1);
bobgiesberts 20:8e1b1efdbb49 122 uint8_t MIN_FREQ = 16 - (8 / f_sensor_min);
bobgiesberts 20:8e1b1efdbb49 123 writeSPIregister(0x04, ((buffer[0] & 0x0F) + (MIN_FREQ << 4)));
bobgiesberts 20:8e1b1efdbb49 124 }
bobgiesberts 20:8e1b1efdbb49 125
bobgiesberts 20:8e1b1efdbb49 126
bobgiesberts 20:8e1b1efdbb49 127
bobgiesberts 20:8e1b1efdbb49 128
bobgiesberts 20:8e1b1efdbb49 129
bobgiesberts 20:8e1b1efdbb49 130
bobgiesberts 20:8e1b1efdbb49 131 float LDC1101::get_Q(void){ return _RPmin * sqrt(_cap/_inductance*1000000); }
bobgiesberts 16:07d0e43c2d12 132
bobgiesberts 19:e205ab9142d8 133
bobgiesberts 19:e205ab9142d8 134 float LDC1101::get_fsensor(void)
bobgiesberts 16:07d0e43c2d12 135 {
bobgiesberts 18:fc9bb81a631f 136 _L_data = get_LHR_Data();
bobgiesberts 18:fc9bb81a631f 137 _fsensor = _fCLKIN * _divider * _L_data/16777216; // (p.26)
bobgiesberts 18:fc9bb81a631f 138 return _fsensor;
bobgiesberts 19:e205ab9142d8 139 }
bobgiesberts 18:fc9bb81a631f 140
bobgiesberts 18:fc9bb81a631f 141
bobgiesberts 19:e205ab9142d8 142 float LDC1101::get_Inductance(void)
bobgiesberts 18:fc9bb81a631f 143 {
bobgiesberts 18:fc9bb81a631f 144 _fsensor = get_fsensor();
bobgiesberts 18:fc9bb81a631f 145 // 1
bobgiesberts 18:fc9bb81a631f 146 // L = --------------------- --> p. 34
bobgiesberts 18:fc9bb81a631f 147 // C * (2*PI*f_sensor)^2
bobgiesberts 20:8e1b1efdbb49 148 _inductance = 1./(_cap * 4*PI*PI*_fsensor*_fsensor); // (p.34)
bobgiesberts 19:e205ab9142d8 149 return _inductance;
bobgiesberts 19:e205ab9142d8 150 }
bobgiesberts 16:07d0e43c2d12 151
bobgiesberts 16:07d0e43c2d12 152
bobgiesberts 18:fc9bb81a631f 153 uint32_t LDC1101::get_LHR_Data(void)
bobgiesberts 16:07d0e43c2d12 154 {
bobgiesberts 18:fc9bb81a631f 155 uint8_t LHR_DATA[3];
bobgiesberts 18:fc9bb81a631f 156 readSPI(LHR_DATA, 0x38, 3); // 0x38 + 0x39 + 0x3A
bobgiesberts 20:8e1b1efdbb49 157 return (LHR_DATA[2]<<16) | (LHR_DATA[1]<<8) | LHR_DATA[0];
bobgiesberts 16:07d0e43c2d12 158 }
bobgiesberts 16:07d0e43c2d12 159
bobgiesberts 16:07d0e43c2d12 160 void LDC1101::readSPI(uint8_t *data, uint8_t address, uint8_t num_bytes)
bobgiesberts 16:07d0e43c2d12 161 {
bobgiesberts 16:07d0e43c2d12 162 // CSB down
bobgiesberts 16:07d0e43c2d12 163 _cs_pin.write(0);
bobgiesberts 16:07d0e43c2d12 164 _spiport.write(address | 0x80); //read flag
bobgiesberts 16:07d0e43c2d12 165 for(int i=0; i < num_bytes ; i++)
bobgiesberts 16:07d0e43c2d12 166 {
bobgiesberts 16:07d0e43c2d12 167 data[i] = _spiport.write(0xFF);
bobgiesberts 16:07d0e43c2d12 168 }
bobgiesberts 16:07d0e43c2d12 169 // CSB up
bobgiesberts 16:07d0e43c2d12 170 _cs_pin.write(1);
bobgiesberts 16:07d0e43c2d12 171 }
bobgiesberts 16:07d0e43c2d12 172
bobgiesberts 16:07d0e43c2d12 173 void LDC1101::writeSPI(uint8_t *data, uint8_t address, uint8_t num_bytes)
bobgiesberts 16:07d0e43c2d12 174 {
bobgiesberts 16:07d0e43c2d12 175 // CSB down
bobgiesberts 16:07d0e43c2d12 176 _cs_pin.write(0);
bobgiesberts 16:07d0e43c2d12 177
bobgiesberts 16:07d0e43c2d12 178 _spiport.write(address);
bobgiesberts 16:07d0e43c2d12 179 for(int i=0; i < num_bytes ; i++)
bobgiesberts 16:07d0e43c2d12 180 {
bobgiesberts 16:07d0e43c2d12 181 _spiport.write(data[i]);
bobgiesberts 16:07d0e43c2d12 182 }
bobgiesberts 16:07d0e43c2d12 183 // CSB up
bobgiesberts 16:07d0e43c2d12 184 _cs_pin.write(1);
bobgiesberts 16:07d0e43c2d12 185 }
bobgiesberts 16:07d0e43c2d12 186
bobgiesberts 16:07d0e43c2d12 187
bobgiesberts 16:07d0e43c2d12 188 // EXTRA test: Get&print values of all variables to verify (to calculate the induction)
bobgiesberts 16:07d0e43c2d12 189 // The data will be printed on the screen using RealTerm: baud 9600.
bobgiesberts 16:07d0e43c2d12 190 // Begin ***********************************************************
bobgiesberts 19:e205ab9142d8 191 float LDC1101::get_fCLKIN() {return _fCLKIN;};
bobgiesberts 19:e205ab9142d8 192 uint8_t LDC1101::get_divider() {return _divider;};
bobgiesberts 19:e205ab9142d8 193 float LDC1101::get_RPmin() {return _RPmin;};
bobgiesberts 19:e205ab9142d8 194 float LDC1101::get_cap() {return _cap;};
bobgiesberts 16:07d0e43c2d12 195 // END ***********************************************************