basic bmp280 lib (mostly adafruit reimplementation) and example

1 files changed, 107 insertions, 0 deletions

diff --git a/lib/bmp280.h b/lib/bmp280.h
new file mode 100644
index 0000000..22472e3
--- /dev/null
+++ b/lib/bmp280.h
@@ -0,0 +1,107 @@
+/*
+ *  spreadspace avr utils
+ *
+ *
+ *  Copyright (C) 2016 Bernhard Tittelbach <bernhard@tittelbach.org>
+ *  appreciative nod to Adafruit for writing a great example, go buy their stuff
+ *
+ *  This file is part of spreadspace avr utils.
+ *
+ *  spreadspace avr utils is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  any later version.
+ *
+ *  spreadspace avr utils is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with spreadspace avr utils. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef SPREADAVR_bmp280_h_INCLUDED
+#define SPREADAVR_bmp280_h_INCLUDED
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define BMP280_AVERAGE_SEA_LEVEL_PRESSURE 1013.25
+#define BMP280_LUFA_SPIO_OPTIONS SPI_SPEED_FCPU_DIV_16  | SPI_MODE_MASTER | SPI_ORDER_MSB_FIRST | SPI_SCK_LEAD_RISING | SPI_SAMPLE_LEADING
+
+/*=========================================================================
+    REGISTERS
+    -----------------------------------------------------------------------*/
+    enum
+    {
+      BMP280_REGISTER_DIG_T1              = 0x88,
+      BMP280_REGISTER_DIG_T2              = 0x8A,
+      BMP280_REGISTER_DIG_T3              = 0x8C,
+
+      BMP280_REGISTER_DIG_P1              = 0x8E,
+      BMP280_REGISTER_DIG_P2              = 0x90,
+      BMP280_REGISTER_DIG_P3              = 0x92,
+      BMP280_REGISTER_DIG_P4              = 0x94,
+      BMP280_REGISTER_DIG_P5              = 0x96,
+      BMP280_REGISTER_DIG_P6              = 0x98,
+      BMP280_REGISTER_DIG_P7              = 0x9A,
+      BMP280_REGISTER_DIG_P8              = 0x9C,
+      BMP280_REGISTER_DIG_P9              = 0x9E,
+
+      BMP280_REGISTER_CHIPID             = 0xD0,
+      BMP280_REGISTER_VERSION            = 0xD1,
+      BMP280_REGISTER_SOFTRESET          = 0xE0,
+
+      BMP280_REGISTER_CAL26              = 0xE1,  // R calibration stored in 0xE1-0xF0
+
+      BMP280_REGISTER_CONTROL            = 0xF4,
+      BMP280_REGISTER_CONFIG             = 0xF5,
+      BMP280_REGISTER_PRESSUREDATA       = 0xF7,
+      BMP280_REGISTER_TEMPDATA           = 0xFA,
+    };
+
+/*=========================================================================*/
+
+
+/*=========================================================================
+    CALIBRATION DATA
+    -----------------------------------------------------------------------*/
+    typedef struct
+    {
+      volatile uint8_t *cs_port;
+      uint8_t  cs_pin;
+      uint16_t dig_T1;
+      int16_t  dig_T2;
+      int16_t  dig_T3;
+
+      uint16_t dig_P1;
+      int16_t  dig_P2;
+      int16_t  dig_P3;
+      int16_t  dig_P4;
+      int16_t  dig_P5;
+      int16_t  dig_P6;
+      int16_t  dig_P7;
+      int16_t  dig_P8;
+      int16_t  dig_P9;
+
+      uint8_t  dig_H1;
+      int16_t  dig_H2;
+      uint8_t  dig_H3;
+      int16_t  dig_H4;
+      int16_t  dig_H5;
+      int8_t   dig_H6;
+    } bmp280_sensor;
+/*=========================================================================*/
+
+
+//make sure to configure the cs_pin as OUTPUT beforehand
+//make sure to configure SPI beforehand
+void bmp280_init(bmp280_sensor *sensor, volatile uint8_t *cs_port, uint8_t cs_pin);
+float bmp280_readTemp(bmp280_sensor *sensor);
+float bmp280_readPressure(bmp280_sensor *sensor);
+float bmp280_readAltitude(bmp280_sensor *sensor, float sealevelp);
+
+
+#endif
\ No newline at end of file