3939
4040#include " SparkFun_SGP30_Library.h"
4141
42- const uint8_t init_air_quality[2 ] = {0x20 , 0x03 };
43- const uint8_t measure_air_quality[2 ] = {0x20 , 0x08 };
44- const uint8_t get_baseline[2 ] = {0x20 , 0x15 };
45- const uint8_t set_baseline[2 ] = {0x20 , 0x1E };
46- const uint8_t set_humidity[2 ] = {0x20 , 0x61 };
47- const uint8_t measure_test[2 ] = {0x20 , 0x32 };
48- const uint8_t get_feature_set_version[2 ] = {0x20 , 0x2F };
49- const uint8_t get_serial_id[2 ] = {0x36 , 0x82 };
50- const uint8_t measure_raw_signals[2 ] = {0x20 , 0x50 };
42+ // const uint8_t init_air_quality[2] = {0x20, 0x03};
43+ // const uint8_t measure_air_quality[2] = {0x20, 0x08};
44+ // const uint8_t get_baseline[2] = {0x20, 0x15};
45+ // const uint8_t set_baseline[2] = {0x20, 0x1E};
46+ // const uint8_t set_humidity[2] = {0x20, 0x61};
47+ // const uint8_t measure_test[2] = {0x20, 0x32};
48+ // const uint8_t get_feature_set_version[2] = {0x20, 0x2F};
49+ // const uint8_t get_serial_id[2] = {0x36, 0x82};
50+ // const uint8_t measure_raw_signals[2] = {0x20, 0x50};
5151
5252// Constructor
5353SGP30::SGP30 () {
@@ -65,6 +65,7 @@ SGP30::SGP30() {
6565}
6666
6767// Start I2C communication using specified port
68+ // Returns SUCCESS if successful or other error code if unsuccessful
6869SGP30ERR SGP30::begin (TwoWire &wirePort) {
6970 _i2cPort = &wirePort; // Grab which port the user wants us to use
7071 _i2cPort->begin ();
@@ -86,7 +87,7 @@ void SGP30::initAirQuality(void) {
8687// Call in regular intervals of 1 second to maintain synamic baseline calculations
8788// CO2 returned in ppm, Total Volatile Organic Compounds (TVOC) returned in ppb
8889// Will give fixed values of CO2=400 and TVOC=0 for first 15 seconds after init
89- // returns ERR_BAD_CRC if CRC8 check failed and SUCCESS if successful
90+ // Returns SUCCESS if successful or other error code if unsuccessful
9091SGP30ERR SGP30::measureAirQuality (void ) {
9192 _i2cPort->beginTransmission (_SGP30Address);
9293 _i2cPort->write (measure_air_quality, 2 ); // command to measure air quality
@@ -110,7 +111,6 @@ SGP30ERR SGP30::measureAirQuality(void) {
110111 _TVOC |= _i2cPort->read (); // store LSB in TVOC
111112 checkSum = _i2cPort->read (); // verify checksum
112113 if (checkSum != _CRC8 (_TVOC)) return ERR_BAD_CRC; // checksum failed
113- _i2cPort->endTransmission ();
114114 CO2 = _CO2; // publish valid data
115115 TVOC = _TVOC; // publish valid data
116116 return SUCCESS;
@@ -121,7 +121,7 @@ SGP30ERR SGP30::measureAirQuality(void) {
121121// Save baseline periodically to non volatile memory
122122// (like EEPROM) to restore after new power up or
123123// after soft reset using setBaseline();
124- // returns ERR_BAD_CRC if CRC8 check failed and SUCCESS if successful
124+ // Returns SUCCESS if successful or other error code if unsuccessful
125125SGP30ERR SGP30::getBaseline (void ) {
126126 _i2cPort->beginTransmission (_SGP30Address);
127127 _i2cPort->write (get_baseline, 2 );
@@ -145,7 +145,6 @@ SGP30ERR SGP30::getBaseline(void) {
145145 _baselineTVOC |= _i2cPort->read (); // store LSB in _baselineTVOC
146146 checkSum = _i2cPort->read (); // verify checksum
147147 if (checkSum != _CRC8 (_baselineTVOC)) return ERR_BAD_CRC; // checksum failed
148- _i2cPort->endTransmission ();
149148 baselineCO2 = _baselineCO2; // publish valid data
150149 baselineTVOC = _baselineTVOC; // publish valid data
151150 return SUCCESS;
@@ -183,7 +182,7 @@ void SGP30::setHumidity(uint16_t humidity) {
183182}
184183
185184// gives feature set version number (see data sheet)
186- // returns ERR_BAD_CRC if CRC8 check failed and SUCCESS if successful
185+ // Returns SUCCESS if successful or other error code if unsuccessful
187186SGP30ERR SGP30::getFeatureSetVersion (void ) {
188187 _i2cPort->beginTransmission (_SGP30Address);
189188 _i2cPort->write (get_feature_set_version, 2 ); // command to get feature version
@@ -203,13 +202,13 @@ SGP30ERR SGP30::getFeatureSetVersion(void) {
203202 _featureSetVersion |= _i2cPort->read (); // store LSB in featureSetVersion
204203 uint8_t checkSum = _i2cPort->read (); // verify checksum
205204 if (checkSum != _CRC8 (_featureSetVersion)) return ERR_BAD_CRC; // checksum failed
206- _i2cPort->endTransmission ();
207205 featureSetVersion = _featureSetVersion; // publish valid data
208206 return SUCCESS;
209207}
210208
211209// Intended for part verification and testing
212210// these raw signals are used as inputs to the onchip calibrations and algorithms
211+ // Returns SUCCESS if successful or other error code if unsuccessful
213212SGP30ERR SGP30::measureRawSignals (void ) {
214213 _i2cPort->beginTransmission (_SGP30Address);
215214 _i2cPort->write (measure_raw_signals, 2 ); // command to measure raw signals
@@ -233,7 +232,6 @@ SGP30ERR SGP30::measureRawSignals(void) {
233232 _ethanol |= _i2cPort->read (); // store LSB in ethanol
234233 checkSum = _i2cPort->read (); // verify checksum
235234 if (checkSum != _CRC8 (_ethanol)) return ERR_BAD_CRC; // checksum failed
236- _i2cPort->endTransmission ();
237235 H2 = _H2; // publish valid data
238236 ethanol = _ethanol; // publish valid data
239237 return SUCCESS;
@@ -248,7 +246,7 @@ void SGP30::generalCallReset(void) {
248246}
249247
250248// readout of serial ID register can identify chip and verify sensor presence
251- // returns ERR_BAD_CRC if CRC8 check failed and SUCCESS if successful
249+ // Returns SUCCESS if successful or other error code if unsuccessful
252250SGP30ERR SGP30::getSerialID (void ) {
253251 _i2cPort->beginTransmission (_SGP30Address);
254252 _i2cPort->write (get_serial_id, 2 ); // command to get serial ID
@@ -267,22 +265,21 @@ SGP30ERR SGP30::getSerialID(void) {
267265 _serialID1 = _i2cPort->read () << 8 ; // store MSB to top of _serialID1
268266 _serialID1 |= _i2cPort->read (); // store next byte in _serialID1
269267 uint8_t checkSum1 = _i2cPort->read (); // verify checksum
268+ if (checkSum1 != _CRC8 (_serialID1)) return ERR_BAD_CRC; // checksum failed
270269 _serialID2 = _i2cPort->read () << 8 ; // store next byte to top of _serialID2
271270 _serialID2 |= _i2cPort->read (); // store next byte in _serialID2
272271 uint8_t checkSum2 = _i2cPort->read (); // verify checksum
272+ if (checkSum2 != _CRC8 (_serialID2)) return ERR_BAD_CRC; // checksum failed
273273 _serialID3 = _i2cPort->read () << 8 ; // store next byte to top of _serialID3
274274 _serialID3 |= _i2cPort->read () ; // store LSB in _serialID3
275275 uint8_t checkSum3 = _i2cPort->read (); // verify checksum
276- if (checkSum1 != _CRC8 (_serialID1)) return ERR_BAD_CRC; // checksum failed
277- if (checkSum2 != _CRC8 (_serialID2)) return ERR_BAD_CRC; // checksum failed
278276 if (checkSum3 != _CRC8 (_serialID3)) return ERR_BAD_CRC; // checksum failed
279277 serialID = ((uint64_t )_serialID1 << 32 ) + ((uint64_t )_serialID2 << 16 ) + ((uint64_t )_serialID3); // publish valid data
280- _i2cPort->endTransmission ();
281278 return SUCCESS;
282279}
283280
284281// Sensor runs on chip self test
285- // returns SUCCESS if successful
282+ // Returns SUCCESS if successful or other error code if unsuccessful
286283SGP30ERR SGP30::measureTest (void ) {
287284 _i2cPort->beginTransmission (_SGP30Address);
288285 _i2cPort->write (measure_test, 2 ); // command to get self test
@@ -304,7 +301,6 @@ SGP30ERR SGP30::measureTest(void) {
304301 uint8_t checkSum = _i2cPort->read (); // verify checksum
305302 if (checkSum != _CRC8 (results)) return ERR_BAD_CRC; // checksum failed
306303 if (results != 0xD400 ) return SELF_TEST_FAIL; // self test results incorrect
307- _i2cPort->endTransmission ();
308304 return SUCCESS;
309305}
310306
0 commit comments