Diff: LIS3DH.cpp

Revision:

0:5d5aac272642

Child:

1:d4d569952436

diff -r 000000000000 -r 5d5aac272642 LIS3DH.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/LIS3DH.cpp	Fri Aug 29 13:27:20 2014 +0000
@@ -0,0 +1,151 @@
+/*
+ * mbed library program 
+ *  LIS3DH MEMS motion sensor: 3-axis "nano" accelerometer, made by STMicroelectronics
+ *      http://www.st-japan.co.jp/web/jp/catalog/sense_power/FM89/SC444/PF250725
+ *
+ * Copyright (c) 2014 Kenji Arai / JH1PJL
+ *  http://www.page.sannet.ne.jp/kenjia/index.html
+ *  http://mbed.org/users/kenjiArai/
+ *      Created: July      14th, 2014 
+ *      Revised: August    29th, 2014
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+ * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
+ * AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include "LIS3DH.h"
+
+LIS3DH::LIS3DH (PinName p_sda, PinName p_scl,
+    uint8_t addr, uint8_t data_rate, uint8_t fullscale) : i2c(p_sda, p_scl) {
+    initialize (addr, data_rate, fullscale);
+}
+
+LIS3DH::LIS3DH (I2C& p_i2c,
+    uint8_t addr, uint8_t data_rate, uint8_t fullscale) : i2c(p_i2c) { 
+    initialize (addr, data_rate, fullscale);
+}
+
+void LIS3DH::initialize (uint8_t addr, uint8_t data_rate, uint8_t fullscale) {
+    // Check acc is available of not
+    acc_addr = addr;
+    dbf[0] = LIS3DH_WHO_AM_I; 
+    i2c.write(acc_addr, dbf, 1); 
+    i2c.read(acc_addr, dbf, 1);
+    if (dbf[0] == I_AM_LIS3DH){
+        acc_ready = 1;
+    } else {
+        acc_ready = 0;
+        return;     // acc chip is NOT on I2C line then terminate
+    }
+    //  Reg.1
+    dbf[0] = LIS3DH_CTRL_REG1;
+    dbf[1] = 0x07;
+    dbf[1] |= data_rate << 4;
+    i2c.write(acc_addr, dbf, 2);
+    //  Reg.4 
+    dbf[0] = LIS3DH_CTRL_REG4;
+    dbf[1] = 0x08;  // High resolution
+    dbf[1] |= fullscale << 4;
+    i2c.write(acc_addr, dbf, 2);
+    switch (fullscale){
+    case LIS3DH_FS_2G:
+        fs_factor = LIS3DH_SENSITIVITY_2G;
+        break;
+    case LIS3DH_FS_4G:
+        fs_factor = LIS3DH_SENSITIVITY_4G;
+        break;
+    case LIS3DH_FS_8G:
+        fs_factor = LIS3DH_SENSITIVITY_8G;
+        break;
+    case LIS3DH_FS_16G:
+        fs_factor = LIS3DH_SENSITIVITY_16G;
+        break;
+    default:
+        ;
+    }   
+}
+
+void LIS3DH::read_reg_data(char *data) {
+    // X,Y & Z
+        // manual said that
+        // In order to read multiple bytes, it is necessary to assert the most significant bit
+        // of the subaddress field.
+        // In other words, SUB(7) must be equal to ‘1’ while SUB(6-0) represents the address
+        // of the first register to be read.
+    dbf[0] = LIS3DH_OUT_X_L | 0x80; 
+    i2c.write(acc_addr, dbf, 1, true); 
+    i2c.read(acc_addr, data, 6, false);
+}
+
+void LIS3DH::read_mg_data(float *dt) {
+char data[6];
+
+    if (acc_ready == 0){
+        dt[0] = 0;
+        dt[1] = 0;
+        dt[2] = 0;
+        return;  
+    }
+    read_reg_data(data);
+    // change data type
+    dt[0] = float(short((data[1] << 8) | data[0])) * fs_factor / 15;
+    dt[1] = float(short((data[3] << 8) | data[2])) * fs_factor / 15;
+    dt[2] = float(short((data[5] << 8) | data[4])) * fs_factor / 15;
+}
+    
+void LIS3DH::read_data(float *dt) {
+char data[6];
+
+    if (acc_ready == 0){
+        dt[0] = 0;
+        dt[1] = 0;
+        dt[2] = 0;
+        return;  
+    }
+    read_reg_data(data);
+    // change data type
+    dt[0] = float(short((data[1] << 8) | data[0])) * fs_factor / 15 * GRAVITY;
+    dt[1] = float(short((data[3] << 8) | data[2])) * fs_factor / 15 * GRAVITY;
+    dt[2] = float(short((data[5] << 8) | data[4])) * fs_factor / 15 * GRAVITY;
+}
+
+uint8_t LIS3DH::read_id() {
+    dbf[0] = LIS3DH_WHO_AM_I; 
+    i2c.write(acc_addr, dbf, 1); 
+    i2c.read(acc_addr, dbf, 1);
+    return (uint8_t)dbf[0];
+}
+
+uint8_t LIS3DH::data_ready() {
+    if (acc_ready == 1){
+        dbf[0] = LIS3DH_STATUS_REG_AUX; 
+        i2c.write(acc_addr, dbf, 1); 
+        i2c.read(acc_addr, dbf, 1);
+        if (!(dbf[0] & 0x01)){
+            return 0;
+        }
+    }
+    return 1;
+}
+
+uint8_t LIS3DH::read_reg(uint8_t addr) {
+    if (acc_ready == 1){
+        dbf[0] = addr; 
+        i2c.write(acc_addr, dbf, 1); 
+        i2c.read(acc_addr, dbf, 1);
+    } else {
+        dbf[0] = 0xff;
+    }
+    return (uint8_t)dbf[0];
+}
+
+void LIS3DH::write_reg(uint8_t addr, uint8_t data) {
+    if (acc_ready == 1){
+        dbf[0] = addr;
+        dbf[1] = data; 
+        i2c.write(acc_addr, dbf, 2); 
+    }
+}