File content as of revision 0:0c17274c3b7c:

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

DigitalOut myled(LED1);

Serial pc(USBTX,USBRX);

#define LOG(...) pc.printf(__VA_ARGS__); pc.printf("\r\n");
#define LOGX(...) pc.printf(__VA_ARGS__);

void printByte(char b) {
   LOG("%d%d%d%d%d%d%d%d",
       (b&0x80)>>7,
       (b&0x40)>>6,
       (b&0x20)>>5,
       (b&0x10)>>4,
       (b&0x08)>>3,
       (b&0x04)>>2,
       (b&0x02)>>1,
       (b&0x01)
   );
}

void sampleMMA8452(MMA8452 *acc, int nsamples) {
   int samples = 0;
   int bufLen = 6;
   char buffer[6];
   memset(&buffer,0x00,bufLen);
   while(samples<nsamples) {
      if(!acc->isXYZReady()) {
         wait(0.01);
         continue;
      }
      memset(&buffer,0x00,bufLen);
      acc->readRawXYZ(buffer);
      LOGX("Sample %d of %d: ",samples,nsamples);
      for(int i=0; i<bufLen; i++) {
         LOGX("%.2x ",buffer[i]);
      }
      LOG(" ");
      samples++;
   }
}

int test() {
    MMA8452 acc(p28, p27, 40000);
    
    acc.debugRegister(MMA8452_CTRL_REG_1);
    
    LOG("Entering standby");
    if(acc.standby()) {
       LOG("Error putting MMA8452 in standby");
       return false;
    }
    
    acc.debugRegister(MMA8452_CTRL_REG_1);
    
    LOG("Activating MMA8452");
    if(acc.activate()) {
       LOG("Error activating MMA8452");
       return false;
    }
    
    // test setting dynamic range
    MMA8452::DynamicRange setRange = MMA8452::DYNAMIC_RANGE_UNKNOWN;
    MMA8452::DynamicRange readRange = MMA8452::DYNAMIC_RANGE_UNKNOWN;
    for(int i=0; i<=(int)MMA8452::DYNAMIC_RANGE_8G; i++) {
       setRange = (MMA8452::DynamicRange)i;
       if(acc.setDynamicRange(setRange)) {
          LOG("Error setting dynamic range. Failing.");
          return false;
       }
       readRange = acc.getDynamicRange();
       if(readRange!=setRange) {
          LOG("Read dynamic range: 0x%x does not match set: 0x%x",readRange,setRange);
          return false;
       }
       LOG("Success on dynamic range %d",i);
    }
    
    // test setting data rate
    for(int i=0; i<=(int)MMA8452::RATE_1_563; i++) {
       if(acc.setDataRate((MMA8452::DataRateHz)i)) {
          LOG("Error setting data rate. Failing.");
          return false;
       }
       if(acc.getDataRate()!=(MMA8452::DataRateHz)i) {
          LOG("Read data rate: 0x%x does not match set: 0x%x",acc.getDataRate(),(MMA8452::DataRateHz)i);
          return false;
       }
       LOG("Success on data rate %d",i);
    }
    
    // set bit depth to 8 and read some values
    LOG("Sampling at BIT_DEPTH_8");
    acc.setBitDepth(MMA8452::BIT_DEPTH_8);
    sampleMMA8452(&acc,10);
    
    // set bit depth to 12 and read some values
    LOG("Sampling at BIT_DEPTH_12");
    acc.setDataRate(MMA8452::RATE_100);
    acc.setBitDepth(MMA8452::BIT_DEPTH_12);
    sampleMMA8452(&acc,10);

    return true;
}

void loop() {
   while(1) {
      wait(1);
   }
}

int main() {
    pc.baud(115200);
    LOG("Begin");
    for(int i=0; i<20; i++) {
       LOG(" ");
    }
    if(!test()) {
       LOG("FAIL.");
       loop();
    }
    LOG("Tests passed");
    loop();
}