Posted on October 28, 2014 at 06:00
Bellow is the i2c reading of the 6 axis registers
x32 is LSM write address
A8 (binary
Regarding the >>4 or /16 i saw that this is used in the ST LSM303dlhc library wich was my reference for the setup code
here is my code and i2c functions
Hello, i dont know how much is this problem related to the i2c comunication wich from my point of view seems to work ok, see bellow the LSM initialization registers where :
0x32 is the write adress of the LSM CTRL_REG1_A (20h) 0x37 - data for setting up CTRL_reg1 with 25hz output data rate, xyz enable axes, normal mode CTRL_REG4_A (23h) 0x00 - sets +/- 2G range, little endian (BLE bit is set 0 ) ''data LSB @ lower address''
Bellow is the i2c reading of the 6 axis registers
x32 is LSM write address
A8 (binary
1
0101000) is 0x28 with the msb set ( 0x28 -0
0101000) After this i send the x33 LSM read command and the chip starts to ouput every acc register values starting with x_lsb ( 0x00) x_msb(0xFD) y_lsb ( 0x00 ) y_msb(0x02) z_lsb(0x80) and the last is z_msb (0x3e )
Regarding the >>4 or /16 i saw that this is used in the ST LSM303dlhc library wich was my reference for the setup code
here is my code and i2c functions
void LSM303_init(){
i2c_send_cmd(awAddr, CTRL_REG1_A, 0x37); // 25hz ODR
i2c_send_cmd(awAddr, CTRL_REG4_A, 0x00);//+2g, little endian
}
void lsm_readAccRaw(int16_t* tempBuf){
uint8_t dataBuffer[6];
i2c_readBuffer(awAddr,dataBuffer,OUT_X_L_A,6);
tempBuf[0]=((dataBuffer[1]<<8)+dataBuffer[0])/16;
tempBuf[1]=((dataBuffer[3]<<8)+dataBuffer[2])/16;
tempBuf[2]=((dataBuffer[4]<<8)+dataBuffer[4])/16;
}
void lsm_readAcc(float* tempBuf){
int16_t aData[3];
lsm_readAccRaw(aData);
tempBuf[0]=aData[0]/1.0; // x axis
tempBuf[1]=aData[1]/1.0; // y axis
tempBuf[2]=aData[2]/1.0; // z axis
}int main(void){
system_init(); // cals for i2c initialization and for other periphs setups
LSM303_init();
float ccc[3];
char txtx[20]
char txty[20]
char txtz[20]
while(1){
lsm_readAcc(ccc);
sprintf(txtx,''%f'',ccc[0]);
sprintf(txty,''%f'',ccc[1]);
sprintf(txtz,''%f'',ccc[2]);
lcd_char(1,1,txtx);
lcd_char(1,1,txty);
lcd_char(1,1,txtz);
delay_ms(200); // 200 ms aprox delay
}
}