main.cpp

00001 /*******************************************************************************
00002  * Copyright (C) 2017 Maxim Integrated Products, Inc., All Rights Reserved.
00003  *
00004  * Permission is hereby granted, free of charge, to any person obtaining a
00005  * copy of this software and associated documentation files (the "Software"),
00006  * to deal in the Software without restriction, including without limitation
00007  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
00008  * and/or sell copies of the Software, and to permit persons to whom the
00009  * Software is furnished to do so, subject to the following conditions:
00010  *
00011  * The above copyright notice and this permission notice shall be included
00012  * in all copies or substantial portions of the Software.
00013  *
00014  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
00015  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
00016  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
00017  * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
00018  * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
00019  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
00020  * OTHER DEALINGS IN THE SOFTWARE.
00021  *
00022  * Except as contained in this notice, the name of Maxim Integrated
00023  * Products, Inc. shall not be used except as stated in the Maxim Integrated
00024  * Products, Inc. Branding Policy.
00025  *
00026  * The mere transfer of this software does not imply any licenses
00027  * of trade secrets, proprietary technology, copyrights, patents,
00028  * trademarks, maskwork rights, or any other form of intellectual
00029  * property whatsoever. Maxim Integrated Products, Inc. retains all
00030  * ownership rights.
00031  *******************************************************************************
00032  */
00033  
00034 
00035 
00036 #include "mbed.h"
00037 #include "max32630fthr.h"
00038 #include "MAX30003.h"
00039 
00040 MAX32630FTHR pegasus(MAX32630FTHR::VIO_3V3);
00041 
00042 void ecg_config(MAX30003 &ecgAFE);
00043 
00044 /* ECG FIFO nearly full callback */
00045 volatile bool ecgFIFOIntFlag = 0; 
00046 void ecgFIFO_callback()  {
00047     
00048     ecgFIFOIntFlag = 1;
00049 
00050 }  
00051 
00052 int main()
00053 {   
00054 
00055     // Constants
00056     const int EINT_STATUS_MASK =  1 << 23;
00057     const int FIFO_OVF_MASK =  0x7;
00058     const int FIFO_VALID_SAMPLE_MASK =  0x0;
00059     const int FIFO_FAST_SAMPLE_MASK =  0x1;
00060     const int ETAG_BITS_MASK = 0x7;
00061     
00062     // Ports and serial connections
00063     Serial pc(USBTX, USBRX);            // Use USB debug probe for serial link
00064     pc.baud(115200);                    // Baud rate = 115200
00065     
00066     DigitalOut rLed(LED1, LED_OFF);      // Debug LEDs
00067     DigitalOut gLed(LED2, LED_OFF);
00068     DigitalOut bLed(LED3, LED_OFF);
00069     
00070     InterruptIn ecgFIFO_int(P5_4);          // Config P5_4 as int. in for the
00071     ecgFIFO_int.fall(&ecgFIFO_callback);    // ecg FIFO almost full interrupt
00072     
00073     SPI spiBus(SPI2_MOSI, SPI2_MISO, SPI2_SCK);     // SPI bus, P5_1 = MOSI, 
00074                                                     // P5_2 = MISO, P5_0 = SCK
00075     
00076     MAX30003 ecgAFE(spiBus, P5_3);          // New MAX30003 on spiBus, CS = P5_3 
00077     ecg_config(ecgAFE);                    // Config ECG 
00078      
00079     
00080     ecgAFE.writeRegister( MAX30003::SYNCH , 0);
00081     
00082     uint32_t ecgFIFO, readECGSamples, idx, ETAG[32], status;
00083     int16_t ecgSample[32];
00084     
00085     while(1) {
00086         
00087         // Read back ECG samples from the FIFO 
00088         if( ecgFIFOIntFlag ) {
00089             
00090             ecgFIFOIntFlag = 0; 
00091             status = ecgAFE.readRegister( MAX30003::STATUS );      // Read the STATUS register
00092              
00093             // Check if EINT interrupt asserted
00094             if ( ( status & EINT_STATUS_MASK ) == EINT_STATUS_MASK ) {     
00095             
00096                 readECGSamples = 0;                        // Reset sample counter
00097                 
00098                 do {
00099                     ecgFIFO = ecgAFE.readRegister( MAX30003::ECG_FIFO );       // Read FIFO
00100                     ecgSample[readECGSamples] = ecgFIFO >> 8;                  // Isolate voltage data
00101                     ETAG[readECGSamples] = ( ecgFIFO >> 3 ) & ETAG_BITS_MASK;  // Isolate ETAG
00102                     readECGSamples++;                                          // Increment sample counter
00103                 
00104                 // Check that sample is not last sample in FIFO                                              
00105                 } while ( ETAG[readECGSamples-1] == FIFO_VALID_SAMPLE_MASK || 
00106                           ETAG[readECGSamples-1] == FIFO_FAST_SAMPLE_MASK ); 
00107                 
00108                 // Check if FIFO has overflowed
00109                 if( ETAG[readECGSamples - 1] == FIFO_OVF_MASK ){                  
00110                     ecgAFE.writeRegister( MAX30003::FIFO_RST , 0); // Reset FIFO
00111                 }
00112                 
00113                 // Print results 
00114                 for( idx = 0; idx < readECGSamples; idx++ ) {
00115                     pc.printf("%6d\r\n", ecgSample[idx]);           
00116                 } 
00117                                
00118             }
00119         }
00120     }
00121 }
00122 
00123 
00124 
00125 
00126 void ecg_config(MAX30003& ecgAFE) { 
00127 
00128     // Reset ECG to clear registers
00129     ecgAFE.writeRegister( MAX30003::SW_RST , 0);
00130     
00131     // General config register setting
00132     MAX30003::GeneralConfiguration_u CNFG_GEN_r;
00133     CNFG_GEN_r.bits.en_ecg = 1;     // Enable ECG channel
00134     CNFG_GEN_r.bits.rbiasn = 1;     // Enable resistive bias on negative input
00135     CNFG_GEN_r.bits.rbiasp = 1;     // Enable resistive bias on positive input
00136     CNFG_GEN_r.bits.en_rbias = 1;   // Enable resistive bias
00137     CNFG_GEN_r.bits.imag = 2;       // Current magnitude = 10nA
00138     CNFG_GEN_r.bits.en_dcloff = 1;  // Enable DC lead-off detection   
00139     ecgAFE.writeRegister( MAX30003::CNFG_GEN , CNFG_GEN_r.all);
00140         
00141     
00142     // ECG Config register setting
00143     MAX30003::ECGConfiguration_u CNFG_ECG_r;
00144     CNFG_ECG_r.bits.dlpf = 1;       // Digital LPF cutoff = 40Hz
00145     CNFG_ECG_r.bits.dhpf = 1;       // Digital HPF cutoff = 0.5Hz
00146     CNFG_ECG_r.bits.gain = 3;       // ECG gain = 160V/V
00147     CNFG_ECG_r.bits.rate = 2;       // Sample rate = 128 sps
00148     ecgAFE.writeRegister( MAX30003::CNFG_ECG , CNFG_ECG_r.all);
00149       
00150     
00151     //R-to-R configuration
00152     MAX30003::RtoR1Configuration_u CNFG_RTOR_r;
00153     CNFG_RTOR_r.bits.en_rtor = 1;           // Enable R-to-R detection
00154     ecgAFE.writeRegister( MAX30003::CNFG_RTOR1 , CNFG_RTOR_r.all);
00155        
00156         
00157     //Manage interrupts register setting
00158     MAX30003::ManageInterrupts_u MNG_INT_r;
00159     MNG_INT_r.bits.efit = 0b00011;          // Assert EINT w/ 4 unread samples
00160     MNG_INT_r.bits.clr_rrint = 0b01;        // Clear R-to-R on RTOR reg. read back
00161     ecgAFE.writeRegister( MAX30003::MNGR_INT , MNG_INT_r.all);
00162     
00163     
00164     //Enable interrupts register setting
00165     MAX30003::EnableInterrupts_u EN_INT_r;
00166     EN_INT_r.all = 0;
00167     EN_INT_r.bits.en_eint = 1;              // Enable EINT interrupt
00168     EN_INT_r.bits.en_rrint = 0;             // Disable R-to-R interrupt
00169     EN_INT_r.bits.intb_type = 3;            // Open-drain NMOS with internal pullup
00170     ecgAFE.writeRegister( MAX30003::EN_INT , EN_INT_r.all);
00171        
00172        
00173     //Dyanmic modes config
00174     MAX30003::ManageDynamicModes_u MNG_DYN_r;
00175     MNG_DYN_r.bits.fast = 0;                // Fast recovery mode disabled
00176     ecgAFE.writeRegister( MAX30003::MNGR_DYN , MNG_DYN_r.all);
00177     
00178     // MUX Config
00179     MAX30003::MuxConfiguration_u CNFG_MUX_r;
00180     CNFG_MUX_r.bits.openn = 0;          // Connect ECGN to AFE channel
00181     CNFG_MUX_r.bits.openp = 0;          // Connect ECGP to AFE channel
00182     ecgAFE.writeRegister( MAX30003::CNFG_EMUX , CNFG_MUX_r.all);
00183        
00184     return;
00185 }  
00186