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Diff: si7021.cpp
- Revision:
- 1:344923bddd4f
- Parent:
- 0:9909c9c7d326
diff -r 9909c9c7d326 -r 344923bddd4f si7021.cpp
--- a/si7021.cpp Tue Sep 12 17:17:03 2017 +0000
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,80 +0,0 @@
-#include "si7021.h"
-
-#define SI7021A20_I2C_ADDR 0x80
-
-#define SI7021A20_CMD_MEAS_RH_HMM 0xE5
-#define SI7021A20_CMD_MEAS_RH_NHMM 0xF5
-#define SI7021A20_CMD_MEAS_TEMP_HMM 0xE3
-#define SI7021A20_CMD_MEAS_TEMP_NHMM 0xF3
-#define SI7021A20_CMD_READ_TEMP 0xE0
-#define SI7021A20_CMD_RESET 0xFE
-#define SI7021A20_CMD_WRITE_USER1 0xE6
-#define SI7021A20_CMD_WRITE_USER2 0xE7
-#define SI7021A20_CMD_WRITE_HEAT_CTRL 0x51
-#define SI7021A20_CMD_READ_HEAT_CTRL 0x11
-#define SI7021A20_CMD_READ_ID1 0xFA0F
-#define SI7021A20_CMD_READ_ID2 0xFCC9
-#define SI7021A20_REGF_ID2_DEV_ID 0x15
-#define SI7021A20_CMD_READ_FW_REV 0x84B8
-
-bool SI7021::_i2c_transfer(int address, void * buff, size_t write_size, size_t read_size)
-{
- bool ok;
- bool expect_response = (read_size != 0);
-
- ok = !_i2c->write(address, (char*)buff, write_size, expect_response);
- if (ok && expect_response)
- ok = !_i2c->read(address, (char*)buff, read_size);
-
- return ok;
-}
-
-/*
-bool SI7021::_validate(void)
-{
- bool ok;
- uint8_t buff[4];
-
- buff[0] = (uint8_t)(SI7021A20_CMD_READ_ID2 >> 8);
- buff[1] = (uint8_t)(SI7021A20_CMD_READ_ID2);
-
- ok = (i2c_transfer(SI7021A20_I2C_ADDR, buff, 2, 1)) &&
- (SI7021A20_REGF_ID2_DEV_ID == buff[0]);
-
- return ok;
-}
-*/
-
-bool SI7021::read(si7021_measurements_t * data) {
- bool ok;
- union {
- char cmd;
- struct {
- uint8_t meas_msb;
- uint8_t meas_lsb;
- };
- } buff;
-
- buff.cmd = SI7021A20_CMD_MEAS_RH_HMM;
- ok = (_i2c_transfer(SI7021A20_I2C_ADDR, &buff, 1, 2));
- if (ok) {
- // Humidity% = measurement * 125/65536 - 6
- int meas_raw = ((int)buff.meas_msb << 8) + buff.meas_lsb;
- data->humidity_PR = (float)meas_raw * (125.0F/65536.0F) - 6.0F;
-// data->humidity = meas_raw / 2 - 1573;
-// data->humidity_norm = 262;
-// printf("<humidityH/r = %f/%d>", Humidity, meas_raw);
-
- buff.cmd = SI7021A20_CMD_READ_TEMP;
- ok = _i2c_transfer(SI7021A20_I2C_ADDR, &buff, 1, 2);
- }
- if (ok) {
- // TempC = measurement * 175.72/65536 - 46.85
- int meas_raw = ((int)buff.meas_msb << 8) + buff.meas_lsb;
- data->temp_C = meas_raw * (175.72/65536.0) - 46.85;
-// data->temp = meas_raw / 2 - 8736;
-// data->temp_norm = 186;
-// printf("<tempC/F/r = %f/%f/%d>", Temp, Temp * 9 / 5 + 32, meas_raw);
- }
- return ok;
-}