Vali Abdrakhmanov
1
Diff: MMA8452.cpp
- Revision:
- 12:172540ff6b8b
- Parent:
- 11:dfd1e0afcb7b
- Child:
- 13:4bd8b4cd479d
--- a/MMA8452.cpp Tue Mar 04 16:23:40 2014 +0000
+++ b/MMA8452.cpp Tue Mar 04 17:50:47 2014 +0000
@@ -25,11 +25,17 @@
// Connect module at I2C address using I2C port pins sda and scl
MMA8452::MMA8452(PinName sda, PinName scl, int frequency) : _i2c(sda, scl) , _frequency(frequency) {
DBG("Creating MMA8452");
+
+ // set I2C frequency
_i2c.frequency(_frequency);
- // setup read and write addresses to avoid duplication
+ // setup read and write addresses for convenience
_readAddress = MMA8452_ADDRESS | 0x01;
_writeAddress = MMA8452_ADDRESS & 0xFE;
+
+ // set some defaults
+ _bitDepth = BIT_DEPTH_UNKNOWN;
+ setBitDepth(BIT_DEPTH_12);
DBG("Done");
}
@@ -40,13 +46,13 @@
// Setting the control register bit 1 to true to activate the MMA8452
int MMA8452::activate() {
// perform write and return error code
- return logicalORRegister(CTRL_REG_1,MMA8452_ACTIVE_MASK);
+ return logicalORRegister(MMA8452_CTRL_REG_1,MMA8452_ACTIVE_MASK);
}
// Setting the control register bit 1 to 0 to standby the MMA8452
int MMA8452::standby() {
// perform write and return error code
- return logicalANDRegister(CTRL_REG_1,MMA8452_STANDBY_MASK);
+ return logicalANDRegister(MMA8452_CTRL_REG_1,MMA8452_STANDBY_MASK);
}
// this reads a register, applies a bitmask with logical AND, sets a value with logical OR,
@@ -102,6 +108,7 @@
}
int MMA8452::setBitDepth(BitDepth depth,int toggleActivation) {
+ _bitDepth = depth;
return maskAndApplyRegister(
MMA8452_CTRL_REG_1,
MMA8452_BIT_DEPTH_MASK,
@@ -110,105 +117,25 @@
);
}
-
-// Get device ID
-int MMA8452::getDeviceID(char *dst)
-{
- return readRegister(WHO_AM_I,dst);
+int MMA8452::isXYZReady() {
+ char rval = 0;
+ if(readRegister(MMA8452_STATUS,&rval)) {
+ return 0;
+ }
+ return (rval&MMA8452_STATUS_ZYXDR_MASK);
}
-
-
-int MMA8452::readRaw(char src, char *dst, int len) {
- // this is the register we want to get data from
- char register_address[1];
- register_address[0] = src;
-
- if(_i2c.write(_writeAddress,register_address,1,true) == 0)
- {
- if(_i2c.read(_readAddress,dst,len)==0)
- {
- return 0;
- }
- }
-
- // failure case, zero array and return error
- for(int i=0; i<len; i++) {
- dst[i] = 0x00;
- }
- return 1;
-}
-
-// Reads x data. This method reads two registers containing the x-axis values from the accelerometer.
-// It takes a 2 byte char array and copies the register values into the buffer. If it fails the char array
-// is set to '0'. It returns '0' success '1' fail. This method does nothing to the registers - just returns
-// the raw data.
-//int MMA8452::read_x(int& xaxisLSB)
-int MMA8452::readRawX(char *xaxis) {
- return readRaw(OUT_X_MSB,xaxis,2);
-}
-
-
-// Reads y data. This method reads two registers containing the x-axis values from the accelerometer.
-// It takes a 2 byte char array and copies the register values into the buffer. If it fails the char array
-// is set to '0'. It returns '0' success '1' fail. This method does nothing to the registers - just returns
-// the raw data.
-
-int MMA8452::readRawY(char *yaxis) {
- return readRaw(OUT_Y_MSB,yaxis,2);
+
+int MMA8452::getDeviceID(char *dst) {
+ return readRegister(MMA8452_WHO_AM_I,dst);
}
-
-
-// Reads z data. This method reads two registers containing the x-axis values from the accelerometer.
-// It takes a 2 byte char array and copies the register values into the buffer. If it fails the char array
-// is set to '0'. It returns '0' success '1' fail. This method does nothing to the registers - just returns
-// the raw data.
-
-int MMA8452::readRawZ(char *zaxis)
-{
- return readRaw(OUT_Z_MSB,zaxis,2);
+int MMA8452::getStatus(char* dst) {
+ return readRegister(MMA8452_STATUS,dst);
}
-
-
-// Reads y data
-int MMA8452::read_y()
-{
- char mcu_address = (MMA8452_ADDRESS <<1);
-
- _i2c.start(); // Start
- _i2c.write(mcu_address); // A write to device 0x98
- _i2c.write(OUT_Y_MSB); // Register to read
- _i2c.start();
- _i2c.write(mcu_address); // Read from device 0x99
- int y = _i2c.read(0); // Read the data
- _i2c.stop();
-
- return y;
-
-}
-
-// Reads z data
-int MMA8452::read_z()
-{
- char mcu_address = (MMA8452_ADDRESS <<1);
-
- _i2c.start(); // Start
- _i2c.write(mcu_address); // A write to device 0x98
- _i2c.write(OUT_Z_MSB); // Register to read
- _i2c.start();
- _i2c.write(mcu_address); // Read from device 0x99
- int z = _i2c.read(0); // Read the data
- _i2c.stop();
-
- return z;
-
-}
-
-
MMA8452::DynamicRange MMA8452::getDynamicRange() {
char rval = 0;
- if(readRegister(MMA8452_CTRL_REG_1,&rval)) {
+ if(readRegister(MMA8452_XYZ_DATA_CFG,&rval)) {
return MMA8452::DYNAMIC_RANGE_UNKNOWN;
}
rval &= (MMA8452_DYNAMIC_RANGE_MASK^0xFF);
@@ -228,35 +155,15 @@
}
// Reads xyz
-int MMA8452::readRawXYZ(char *x, char *y, char *z)
-{
-
-
- char mcu_address = (MMA8452_ADDRESS <<1);
- char register_buffer[6] ={0,0,0,0,0,0};
- const char Addr_X = OUT_X_MSB;
- _i2c.write(mcu_address); // A write to device 0x98
- _i2c.write(MMA8452_ADDRESS, &Addr_X, 1); // Pointer to the OUT_X_MSB register
-
- if(_i2c.write(mcu_address,&Addr_X,1) == 0)
- {
- if(_i2c.read(mcu_address,register_buffer,6) == 0)
- {
- *x = register_buffer[1];
- *y = register_buffer[3];
- *z = register_buffer[5];
- return 0; // yahoooooo
- }
- else
- {
- return 1; // failed oh nooo!
- }
- }
- else
- {
- return 1; // failed oh nooo!
- }
-
+int MMA8452::readRawXYZ(char *dst) {
+ if(_bitDepth==BIT_DEPTH_UNKNOWN) {
+ return 1;
+ }
+ int readLen = 3;
+ if(_bitDepth==BIT_DEPTH_12) {
+ readLen = 6;
+ }
+ return readRegister(MMA8452_OUT_X_MSB,dst,readLen);
}
// apply an AND mask to a register. read register value, apply mask, write it back
@@ -284,7 +191,6 @@
return writeRegister(addr,value);
}
-
// apply an OR mask to a register. read register value, apply mask, write it back
int MMA8452::logicalXORRegister(char addr, char mask) {
char value = 0;
@@ -367,7 +273,7 @@
// get register value
char v = 0;
if(readRegister(reg,&v)) {
- DBG("Error reading control register");
+ DBG("Error reading specified register");
return;
}
// print out details
@@ -410,6 +316,18 @@
}
break;
+ case MMA8452_STATUS:
+ DBG("STATUS has value: 0x%x",v);
+ DBG(" 7 ZYXOW: %d",(v&0x80)>>7);
+ DBG(" 6 ZOW: %d", (v&0x40)>>6);
+ DBG(" 5 YOW: %d", (v&0x20)>>5);
+ DBG(" 4 XOW: %d", (v&0x10)>>4);
+ DBG(" 3 ZYXDR: %d",(v&0x08)>>3);
+ DBG(" 2 ZDR: %d", (v&0x04)>>2);
+ DBG(" 1 YDR: %d", (v&0x02)>>1);
+ DBG(" 0 XDR: %d", (v&0x01));
+ break;
+
default:
DBG("Unknown register address: 0x%x",reg);
break;