Ashley Mills / MMA8452

Library for driving the MMA8452 accelerometer over I2C

Dependents:   MMA8452_Test MMA8452_Demo Dualing_Tanks IMU-Controlled_MP3_Player ... more

Here is a simple example:

#include "mbed.h"
#include "MMA8452.h"

int main() {
   Serial pc(USBTX,USBRX);
   pc.baud(115200);
   double x = 0, y = 0, z = 0;

   MMA8452 acc(p28, p27, 40000);
   acc.setBitDepth(MMA8452::BIT_DEPTH_12);
   acc.setDynamicRange(MMA8452::DYNAMIC_RANGE_4G);
   acc.setDataRate(MMA8452::RATE_100);
   
   while(1) {
      if(!acc.isXYZReady()) {
         wait(0.01);
         continue;
      }
      acc.readXYZGravity(&x,&y,&z);
      pc.printf("Gravities: %lf %lf %lf\r\n",x,y,z);
   }
}

An easy way to test that this actually works is to run the loop above and hold the MMA8452 parallel to the ground along the respective axis (and upsidedown in each axis). You will see 1G on the respective axis and 0G on the others.

Diff: MMA8452.cpp

Revision:
21:a92a632a0cc7
Parent:
20:d55e9d7eb17e
--- a/MMA8452.cpp	Fri Mar 07 11:55:30 2014 +0000
+++ b/MMA8452.cpp	Fri Mar 07 14:53:40 2014 +0000
@@ -127,9 +127,9 @@
    );
 }
 
-char MMA8452::getMaskedRegister(int reg, char mask) {
+char MMA8452::getMaskedRegister(int addr, char mask) {
    char rval = 0;
-   if(readRegister(reg,&rval)) {
+   if(readRegister(addr,&rval)) {
       return 0;
    }
    return (rval&mask);