Hi Everyone, As I am frequently asked for a simple bare metal example code for the Xtrinsic MMA8451Q digital accelerometer, I would like to share here one of my examples I have created for this part while working with the Freescale FRDM-KL25Z platform. This example illustrates: 1. Initialization of the MKL25Z128 MCU (mainly I2C and PORT modules). 2. Initialization of the accelerometer to achieve the highest resolution. 3. Simple offset calibration based on the AN4069. 4. Output data reading using an interrupt technique. 5. Conversion of the output values from registers 0x01 – 0x06 to real acceleration values in g’s. 6. Visualization of the output values in the FreeMASTER tool. 1. According to the schematic, the INT1 output of the MMA8451Q is connected to the PTA14 pin of the KL25Z MCU and both SCL and SDA lines are connected to the I2C0 module (PTE24 and PTE25 pins). The MCU is, therefore, configured as follows: void MCU_Init(void) {      //I2C0 module initialization      SIM_SCGC4 |= SIM_SCGC4_I2C0_MASK;        // Turn on clock to I2C0 module      SIM_SCGC5 |= SIM_SCGC5_PORTE_MASK;       // Turn on clock to Port E module      PORTE_PCR24 = PORT_PCR_MUX(5);           // PTE24 pin is I2C0 SCL line      PORTE_PCR25 = PORT_PCR_MUX(5);           // PTE25 pin is I2C0 SDA line      I2C0_F  = 0x14;                          // SDA hold time = 2.125us, SCL start hold time = 4.25us, SCL stop hold time = 5.125us *      I2C0_C1 = I2C_C1_IICEN_MASK;             // Enable I2C0 module           //Configure the PTA14 pin (connected to the INT1 of the MMA8451Q) for falling edge interrupts      SIM_SCGC5 |= SIM_SCGC5_PORTA_MASK;       // Turn on clock to Port A module      PORTA_PCR14 |= (0|PORT_PCR_ISF_MASK|     // Clear the interrupt flag                        PORT_PCR_MUX(0x1)|     // PTA14 is configured as GPIO                        PORT_PCR_IRQC(0xA));   // PTA14 is configured for falling edge interrupts           //Enable PORTA interrupt on NVIC      NVIC_ICPR |= 1 << ((INT_PORTA - 16)%32);      NVIC_ISER |= 1 << ((INT_PORTA - 16)%32); } 2. At the beginning of the initialization, all accelerometer registers are reset to their default values by setting the RST bit of the CTRL_REG2 register. The dynamic range is set to ±2g and to achieve the highest resolution, the LNOISE bit is set and the lowest ODR (1.56Hz) and the High Resolution mode are selected (more details in AN4075). void Accelerometer_Init (void) {      unsigned char reg_val = 0;        I2C_WriteRegister(MMA845x_I2C_ADDRESS, CTRL_REG2, 0x40);           // Reset all registers to POR values          do            // Wait for the RST bit to clear      {         reg_val = I2C_ReadRegister(MMA845x_I2C_ADDRESS, CTRL_REG2) & 0x40;      }  while (reg_val);        I2C_WriteRegister(MMA845x_I2C_ADDRESS, XYZ_DATA_CFG_REG, 0x00);    // +/-2g range -> 1g = 16384/4 = 4096 counts      I2C_WriteRegister(MMA845x_I2C_ADDRESS, CTRL_REG2, 0x02);           // High Resolution mode      I2C_WriteRegister(MMA845x_I2C_ADDRESS, CTRL_REG1, 0x3D);           // ODR = 1.56Hz, Reduced noise, Active mode   } 3. A simple offset calibration method is implemented according to the AN4069. At the end of the calibration routine, the DRDY interrupt is enabled and routed to the INT1 interrupt pin that is configured to be a push-pull, active-low output. void Calibrate (void) {      unsigned char reg_val = 0;            while (!reg_val)           // Wait for a first set of data               {         reg_val = I2C_ReadRegister(MMA845x_I2C_ADDRESS, STATUS_REG) & 0x08;      }               I2C_ReadMultiRegisters(MMA845x_I2C_ADDRESS, OUT_X_MSB_REG, 6, AccData);           // Read data output registers 0x01-0x06                                                 Xout_14_bit = ((short) (AccData[0]<<8 | AccData[1])) >> 2;           // Compute 14-bit X-axis output value      Yout_14_bit = ((short) (AccData[2]<<8 | AccData[3])) >> 2;           // Compute 14-bit Y-axis output value      Zout_14_bit = ((short) (AccData[4]<<8 | AccData[5])) >> 2;           // Compute 14-bit Z-axis output value                                          Xoffset = Xout_14_bit / 8 * (-1);        // Compute X-axis offset correction value      Yoffset = Yout_14_bit / 8 * (-1);        // Compute Y-axis offset correction value      Zoffset = (Zout_14_bit - SENSITIVITY_2G) / 8 * (-1);          // Compute Z-axis offset correction value                                          I2C_WriteRegister(MMA845x_I2C_ADDRESS, CTRL_REG1, 0x00);             // Standby mode to allow writing to the offset registers       I2C_WriteRegister(MMA845x_I2C_ADDRESS, OFF_X_REG, Xoffset);              I2C_WriteRegister(MMA845x_I2C_ADDRESS, OFF_Y_REG, Yoffset);       I2C_WriteRegister(MMA845x_I2C_ADDRESS, OFF_Z_REG, Zoffset);       I2C_WriteRegister(MMA845x_I2C_ADDRESS, CTRL_REG3, 0x00);             // Push-pull, active low interrupt      I2C_WriteRegister(MMA845x_I2C_ADDRESS, CTRL_REG4, 0x01);             // Enable DRDY interrupt      I2C_WriteRegister(MMA845x_I2C_ADDRESS, CTRL_REG5, 0x01);             // DRDY interrupt routed to INT1 - PTA14      I2C_WriteRegister(MMA845x_I2C_ADDRESS, CTRL_REG1, 0x3D);             // ODR = 1.56Hz, Reduced noise, Active mode  } 4. In the ISR, only the interrupt flag is cleared and the DataReady variable is set to indicate the arrival of new data. void PORTA_IRQHandler() {      PORTA_PCR14 |= PORT_PCR_ISF_MASK;            // Clear the interrupt flag      DataReady = 1;      } 5. The output values from accelerometer registers 0x01 – 0x06 are first converted to signed 14-bit values and afterwards to real values in g’s. if (DataReady)             // Is a new set of data ready? {                 DataReady = 0;                                                                                                                      I2C_ReadMultiRegisters(MMA845x_I2C_ADDRESS, OUT_X_MSB_REG, 6, AccData);           // Read data output registers 0x01-0x06             Xout_14_bit = ((short) (AccData[0]<<8 | AccData[1])) >> 2;           // Compute 14-bit X-axis output value      Yout_14_bit = ((short) (AccData[2]<<8 | AccData[3])) >> 2;           // Compute 14-bit Y-axis output value      Zout_14_bit = ((short) (AccData[4]<<8 | AccData[5])) >> 2;           // Compute 14-bit Z-axis output value                      Xout_g = ((float) Xout_14_bit) / SENSITIVITY_2G;              // Compute X-axis output value in g's      Yout_g = ((float) Yout_14_bit) / SENSITIVITY_2G;              // Compute Y-axis output value in g's      Zout_g = ((float) Zout_14_bit) / SENSITIVITY_2G;              // Compute Z-axis output value in g's                                   } 6. The calculated values can be watched in the "Variables" window on the top right of the Debug perspective or in the FreeMASTER application. To view both the 14-bit and real values in the FreeMASTER application, some USBDM drivers need to be first installed on your computer. They are available for download from SourceForge. Erich Styger described their installation in this tutorial. In addition to that, the USBDM_OpenSDA application that provides both debugging and a virtual serial port needs to be loaded into the MK20 debugger chip on the FRDM-KL25Z board. This installation follows the usual FRDM-KL25Z bootloader process: Unplug the FRDM-KL25Z board. Whilst holding the SW1/RST switch depressed plug in the FRDM-KL25Z board. The green LED should start blinking at a rate of about 1Hz. Open a file explorer and locate the USB drive that has now appeared. It will have the drive name "BOOTLOADER". Drag the file USBDM_OpenSDA.sx to the USB drive and wait a short while. The OpenSDA firmware on the FRDM-KL25Z board will program the USBDM firmware into the MK20 debugger chip on the board. Remove and re-plug the FRDM-KL25Z board. The board will now appear as a USBDM device. Attached you can find the complete source code written in the CW for MCU's v10.5 as well as the FreeMASTER project. So make it, test it and keep in touch... Regards, Tomas

System for environmental noise monitoring, with capacity of data storage at micro sd memory, option of wireless communication with computer and other systems to form a sensor network. This project consists on the design of a noise pollution level metering system, using a sound sensor board. Its value in the health area lies in prevents ear diseases and other conditions due noise pollution. The capability to create a sensor network, allows generating a statistical study, as well a more detailed study of the noise propagation patterns or the noise pollution source itself. The acknowledgment of the noise level enable to know the actions required to decrease this kind of pollution without expose human ear. It has several source codes: the main folder is that called "SSProyectoSonometro" which contains the three modes of operation. The other folder called "XbeePracticaDataSender" contains the source code for reception and sending data by Zigbee communication. The video has to be watched with the best quality that Youtube allows for a good viewing.

Using this document you can simply introduce the measured data from the MPL3115A2 and you will get the expected output data for Altimeter/Barometric Pressure and Temperature measurements.

This is a PDF version of the Sensor Fusion tutorial I gave at the RoboBusiness conference in Santa Clara on 24 October.

     The MC12311 is a highly-integrated, cost-effective, system-in-package (SIP), sub-1GHz wireless node solution with an FSK, GFSK, MSK, or OOK modulation-capable transceiver and low-power HCS08 8-bit microcontroller. The highly integrated RF transceiver operates over a wide frequency range including 315 MHz, 433 MHz, 470 MHz, 868 MHz, 915 MHz, 928 MHz, and 955 MHz in the license-free Industrial, Scientific and Medical (ISM) frequency bands.      The MPXY8600 is a sensor for use in applications that monitor tire pressure and temperature. It contains the pressure and temperature sensors, an X-axis and a Z-axis accelerometer, a microcontroller, an LF receiver and an RF transmitter all within a single package.      This document offer customers to utilize Freescale MPXY8600 as transmitter and MC12311 as receiver to form 315MHz, 433.92MHz TPMS transmitter and receiver solution.

Ever wondered about the pin styles for pressure sensors in their data sheets? Well then here are some useful notes. The difference between style 1 and style 2 in the package dimensions is due to the two main families of pressure sensors Freescale offers. Style 1 is usually applicable for all MPXx10, MPXx53 and MPXx2000-series SOP Type package pressure sensors featuring differential outputs. Style 2 is applicable for all MPXx4000-series, MPXx5000-series, MPXx6000-series, MPXx7000-series integrated devices in surface mount packages featuring single ended outputs. E.g. for MPXV7002DP case no. 1351-01 SMALL OUTLINE PACKAGE

Hi Everyone, In one of my previous documents I presented a simple example code/demo that reads both the altitude and temperature data from the Xtrinsic MPL3115A2 pressure sensor and visualizes them using the FreeMASTER tool via USBDM interface. This time I would like to share another example with the MPL3115A2 programmed to measure pressure (barometer mode) and temperature. The Freescale FRDM-KL25Z board coupled with the Xtrinsic MEMS sensors board was used for this project. The initialization of the Kinetis KL25Z128 MCU remains the same, the only small change is in the initialization of the MPL3115A2, this time the barometer mode is selected with the OSR of 128. void MPL3115A2_Init (void) {      unsigned char reg_val = 0;                 I2C_WriteRegister(MPL3115A2_I2C_ADDRESS, CTRL_REG1, 0x04);               // Reset all registers to POR values          do            // Wait for the RST bit to clear      {        reg_val = I2C_ReadRegister(MPL3115A2_I2C_ADDRESS, CTRL_REG1) & 0x04;      } while (reg_val);      I2C_WriteRegister(MPL3115A2_I2C_ADDRESS, PT_DATA_CFG_REG, 0x07);         // Enable data flags      I2C_WriteRegister(MPL3115A2_I2C_ADDRESS, CTRL_REG3, 0x11);               // Open drain, active low interrupts      I2C_WriteRegister(MPL3115A2_I2C_ADDRESS, CTRL_REG4, 0x80);               // Enable DRDY interrupt      I2C_WriteRegister(MPL3115A2_I2C_ADDRESS, CTRL_REG5, 0x00);               // DRDY interrupt routed to INT2 - PTD3      I2C_WriteRegister(MPL3115A2_I2C_ADDRESS, CTRL_REG1, 0x39);               // Active barometer mode, OSR = 128           } In the main loop, both pressure and temperature data are read and then calculated as follows. if (DataReady)          // Is a new set of data ready? {                  DataReady = 0;           /* Read both the pressure and temperature data */                       OUT_P_MSB = I2C_ReadRegister(MPL3115A2_I2C_ADDRESS, OUT_P_MSB_REG);             OUT_P_CSB = I2C_ReadRegister(MPL3115A2_I2C_ADDRESS, OUT_P_CSB_REG);             OUT_P_LSB = I2C_ReadRegister(MPL3115A2_I2C_ADDRESS, OUT_P_LSB_REG);             OUT_T_MSB = I2C_ReadRegister(MPL3115A2_I2C_ADDRESS, OUT_T_MSB_REG);             OUT_T_LSB = I2C_ReadRegister(MPL3115A2_I2C_ADDRESS, OUT_T_LSB_REG);                                  /* Get pressure, the 20-bit measurement in Pascals is comprised of an unsigned integer component and a fractional component.      The unsigned 18-bit integer component is located in OUT_P_MSB, OUT_P_CSB and bits 7-6 of OUT_P_LSB.      The fractional component is located in bits 5-4 of OUT_P_LSB. Bits 3-0 of OUT_P_LSB are not used.*/                       Pressure = (float) (((OUT_P_MSB << 16) | (OUT_P_CSB << 😎 | (OUT_P_LSB & 0xC0)) >> 6) + (float) ((OUT_P_LSB & 0x30) >> 4) * 0.25;                          /* Get temperature, the 12-bit temperature measurement in °C is comprised of a signed integer component and a fractional component.      The signed 8-bit integer component is located in OUT_T_MSB. The fractional component is located in bits 7-4 of OUT_T_LSB.      Bits 3-0 of OUT_T_LSB are not used. */                          Temperature = (float) ((signed char) OUT_T_MSB) + (float) (OUT_T_LSB >> 4) * 0.0625;                                                        }         As usual, the calculated values can be watched in the "Variables" window on the top right of the Debug perspective or in the FreeMASTER application. The complete source code written in the CW 10.3 as well as the FreeMASTER project is attached to this document. If there are any questions regarding this simple application, please feel free to ask below. Your feedback or suggestions are also welcome. Regards, Tomas

Following my previous post on the Element 14 triple sensor board, I intergrated Freemaster and made a few changes to my CW project. I hence made a new stand-alone file called 'E14_freemaster" that uses data from the three sensorS (MMA8491,MAG3110,MPL3115A2) boards to draw graphs on freemaster. I have also included a tutorial (FREEMASTER AND THE TRIPLE SENSOR) on how to use freemaster with the triple sensor project and suggesions on further improvements.

SOP Top Side Port Package_1369-01  

Hi Everyone,   I would like to share a simple example code/demo that reads both the altitude and temperature data from the Xtrinsic MPL3115A2 pressure sensor and visualizes them using the FreeMASTER tool via USBDM interface. I have used recently released Xtrinsic MEMS sensors board that features three types of Xtrinsic sensors including the MPL3115A2 and is fully compatible with the Freescale FRDM-KL25Z platform.   According to the User Manual, both interrupt pins of the MPL3115A2 are connected to the PTD3 pin of KL25Z MCU through a 4.7K pull-up resistor as well as both SCL and SDA lines that are connected to the I2C1 module (PTE1 and PTE0 pins) on the KL25Z. The MCU is, therefore, configured as follows: void MCU_Init(void) {        //I2C1 module initialization            SIM_SCGC4 |= SIM_SCGC4_I2C1_MASK;        // Turn on clock to I2C1 module        SIM_SCGC5 |= SIM_SCGC5_PORTE_MASK;       // Turn on clock to Port E module        PORTE_PCR1 = PORT_PCR_MUX(6);            // PTE1 pin is I2C1 SCL line        PORTE_PCR0 = PORT_PCR_MUX(6);            // PTE0 pin is I2C1 SDA line        I2C1_F  = 0x14;                          // SDA hold time = 2.125us, SCL start hold time = 4.25us, SCL stop hold time = 5.125us        I2C1_C1 = I2C_C1_IICEN_MASK;             // Enable I2C1 module          //Configure the PTD3 pin (connected to the INT2 of the MPL3115A2) for falling edge interrupt          SIM_SCGC5 |= SIM_SCGC5_PORTD_MASK;       // Turn on clock to Port D module        PORTD_PCR3 |= (0|PORT_PCR_ISF_MASK|      // Clear the interrupt flag        PORT_PCR_MUX(0x1)|                       // PTD3 is configured as GPIO        PORT_PCR_IRQC(0xA));                     // PTD3 is configured for falling edge interrupts                     //Enable PORTD interrupt on NVIC        NVIC_ICPR |= 1 << ((INT_PORTD - 16)%32);        NVIC_ISER |= 1 << ((INT_PORTD - 16)%32); }   In the ISR, only the interrupt flag is cleared and the DataReady variable is set to indicate the arrival of new data.   void PORTD_IRQHandler() {        PORTD_PCR3 |= PORT_PCR_ISF_MASK;         // Clear the interrupt flag        DataReady = 1; } At the beginning of the initialization, all MPL3115A2 registers are reset to their default values by setting the RST bit of the CTRL_REG1 register.The DRDY interrupt is enabled and routed to the INT2 pin that is configured to be an open-drain, active-low output. During the initialization of the MPL3115A2, the OSR ratio of 128 is selected and finally the part goes into Active Altimeter mode.   void MPL3115A2_Init (void) {        unsigned char reg_val = 0;                    I2C_WriteRegister(MPL3115A2_I2C_ADDRESS, CTRL_REG1, 0x04);                        // Reset all registers to POR values             do            // Wait for the RST bit to clear        {           reg_val = I2C_ReadRegister(MPL3115A2_I2C_ADDRESS, CTRL_REG1) & 0x04;        }  while (reg_val);        I2C_WriteRegister(MPL3115A2_I2C_ADDRESS, PT_DATA_CFG_REG, 0x07);                  // Enable data flags        I2C_WriteRegister(MPL3115A2_I2C_ADDRESS, CTRL_REG3, 0x11);                        // Open drain, active low interrupts        I2C_WriteRegister(MPL3115A2_I2C_ADDRESS, CTRL_REG4, 0x80);                        // Enable DRDY interrupt        I2C_WriteRegister(MPL3115A2_I2C_ADDRESS, CTRL_REG5, 0x00);                        // DRDY interrupt routed to INT2 - PTD3        I2C_WriteRegister(MPL3115A2_I2C_ADDRESS, CTRL_REG1, 0xB9);                        // Active altimeter mode, OSR = 128 }   In the main loop, the DataReady variable is periodically checked and if it is set, both altitude and temperature data are read and then calculated.   if (DataReady)          // Is a new set of data ready? {                   DataReady = 0;                  OUT_P_MSB = I2C_ReadRegister(MPL3115A2_I2C_ADDRESS, OUT_P_MSB_REG);        // High byte of integer part of altitude,        OUT_P_CSB = I2C_ReadRegister(MPL3115A2_I2C_ADDRESS, OUT_P_CSB_REG);        // Low byte of integer part of altitude        OUT_P_LSB = I2C_ReadRegister(MPL3115A2_I2C_ADDRESS, OUT_P_LSB_REG);        // Decimal part of altitude in bits 7-4        OUT_T_MSB = I2C_ReadRegister(MPL3115A2_I2C_ADDRESS, OUT_T_MSB_REG);        // Integer part of temperature        OUT_T_LSB = I2C_ReadRegister(MPL3115A2_I2C_ADDRESS, OUT_T_LSB_REG);        // Decimal part of temperature in bits 7-4                           /* Get altitude, the 20-bit measurement in meters is comprised of a signed integer component and        a fractional component. The signed 16-bit integer component is located in OUT_P_MSB and OUT_P_CSB.        The fraction component is located in bits 7-4 of OUT_P_LSB. Bits 3-0 of OUT_P_LSB are not used */                       Altitude = (float) ((short) ((OUT_P_MSB << 😎 | OUT_P_CSB)) + (float) (OUT_P_LSB >> 4) * 0.0625;                     /* Get temperature, the 12-bit temperature measurement in °C is comprised of a signed integer component and        a fractional component. The signed 8-bit integer component is located in OUT_T_MSB. The fractional component        is located in bits 7-4 of OUT_T_LSB. Bits 3-0 of OUT_T_LSB are not used. */                           Temperature = (float) ((signed char) OUT_T_MSB) + (float) (OUT_T_LSB >> 4) * 0.0625;                                                              }   The calculated values can be watched in the "Variables" window on the top right of the Debug perspective or in the FreeMASTER application. Attached you can find the complete source code written in the CW 10.3 as well as the FreeMASTER project.   If there are any questions regarding this simple application, please feel free to ask below. Your feedback or suggestions are also welcome.   Regards, Tomas Original Attachment has been moved to: FreeMASTER---XTRINSIC-SENSORS-EVK_MPL3115A2_BasicReadUsingInterrupt.zip Original Attachment has been moved to: XTRINSIC-SENSORS-EVK_MPL3115A2_BasicReadUsingInterrupt.zip

SOP Dual Side Port Package_1351-01

This document provides answers for some of the common questions received by the Technical Support team about some inquiries with the usage of the CRTOUCH GUI.

SOP Axial Port Package_482A-01

Video clip associated with "Android as a Platform for Sensor Fusion Education and Evaluation" presented at 2013 Sensors Expo & Conference by Michael Stanley.

"Android as a Platform for Sensor Fusion Education and Evaluation" presented at 2013 Sensors Expo & Conference by Michael Stanley.