int main()
{
//create i2c bus. the 0 indicates pull up resistors are present on the i2c line
DofBus = i2c_newbus(DofSCL, DofSDA, 0);
unsigned char ID = 2;
int val = i2c_in(DofBus, GyroAddr, 0x00, 1, (unsigned char*)ID, 1);
//get device ID with i2c read
print("ID readback: 0x%x", ID);
char temp[5];
pause(100); //allow gyro clocks to stabalise
//start hyperterminal menu
hyperterminal();
while(1)
{
}
return 0;
}
short ee_readShort(int addr)
{
while(lockset(eei2cLock));
int value;
i2c_in(st_eeprom, 0x50, addr, 2, (unsigned char*) &value, 2);
lockclr(eei2cLock);
return value;
}
unsigned char* ee_get_str(unsigned char *s, int n, int addr)
{
if(!st_eeInitFlag) ee_init();
// const unsigned char addrArray[] = {(char)(addr >> 8), (char)(addr&0xFF)};
// i2c_in(st_eeprom, 0xA0, addrArray, 2, s, n);
i2c_in(st_eeprom, 0x50, addr, 2, s, n);
return s;
}
int ee_getInt(int addr)
{
if(!st_eeInitFlag) ee_init();
//unsigned char val[4] = {0, 0, 0, 0};
int value;
// const unsigned char addrArray[] = {(char)(addr >> 8), (char)(addr&0xFF)};
// i2c_in(st_eeprom, 0xA0, addrArray, 2, val, 4);
i2c_in(st_eeprom, 0x50, addr, 2, (unsigned char*) &value, 4);
// int value = (int)((int)(val[0]) | (int)(val[1] << 8) | (int)(val[2] << 16) | (int)(val[3] << 24));
return value;
}
float ee_get_float32(int addr)
{
if(!eeInitFlag) ee_init();
//int value = 0;
unsigned char value[4] = {0, 0, 0, 0};
unsigned char addrArray[] = {(char)(addr >> 8), (char)(addr & 0xFF)};
i2c_in(eeprom, 0xA0, addrArray, 2, value, 4);
float fpVal;
memcpy(&fpVal, &value, sizeof value);
return fpVal;
}
int accel(int axis)
{
if(!st_eeInitFlag) ee_init();
unsigned char val = 0;
while(lockset(eei2cLock));
i2c_in (st_eeprom, MMA7660_I2C,
axis, 1, &val, 1);
i2c_stop(st_eeprom);
lockclr(eei2cLock);
int g100 = raw2g100(val);
if(axis == AY) g100 = -g100;
return g100;
}
void I2C_ByteRead(I2C_ADDR_t slaveAddress, uint8_t reg, uint8_t* data)
{
uint8_t num_bytes;
uint8_t size = 0;
if (reg > 0)
{
size = sizeof(reg);
}
lockset(lock);
while (i2c_busy(i2c_bus, slaveAddress))
{
;
}
num_bytes = i2c_in(i2c_bus, slaveAddress, reg, size, data, 1);
lockclr(lock);
print("\t\tRead addr %02x, reg %02x, data %02x, total %d\n", slaveAddress, reg, *data, num_bytes);
}
int main() // Main function
{
eeBus = i2c_newbus(28, 29, 0); // Set up I2C bus, get bus ID
// Use eeBus to write to device
i2c_out(eeBus, 0b1010000, // with I2C address 0b1010000,
32768, 2, "abcdefg", 8); // send address 32768 (2 bytes)
// and "abc..." data (8 bytes)
while(i2c_busy(eeBus, 0b1010000)); // Wait for EEPROM to finish
char testStr[] = {0, 0, 0, 0, 0, 0, 0, 0}; // Set up test string
// Use eeBus to read from device
i2c_in(eeBus, 0b1010000, // with I2C address 0b1010000,
32768, 2, testStr, 8); // send address 32768 (2 bytes)
// data in to testStr (8 bytes)
print("testStr = %s \n", testStr); // Display result
}
void hyperterminal(void)
{
int menu_no; //hyperterminal switch variable
char reg_in[1]; //char to store single byte read in by I2C
char reg_out[1]; //char to store single byte to be written to part with I2C
int x, y, z; //Stores XYZ output after conversion from reister values
int dt, t; //stores timing values: t holds a clock value, dt is compared to it
char buffer[6]; //buffer which stores 56 register read backs from a multibyte i2c readback
int tic = CNT;
float temp = 0;
float sum = 0;
float xsum = 0;
float ysum = 0;
float zsum = 0;
float prev = 0;
float current = 0;
while(1)
{
//menu options
print("\n\nSelect a menu option with a number, followed by enter\n");
print("1. Exit hyperterminal \n");
print("2. Read back ID register\n");
print("3. Setup: set clock to Xgyro, sample rate div to 9 (100Hz output), filter 98Hz\n");
print("4. Stream 5 seconds of data\n");
print("5. Stream 30 seconds of data \n");
print("6. 2 second bias calculation\n");
print("7. 10 second cumulative angle calculation\n");
print("8. Timing readout debugger\n");
//get user input. Must be a number! follow with enter
scanf("%d", &menu_no);
switch(menu_no)
{
case 1:
return; //Exit hyperterminal
break;
case 2: //dev ID readback
i2c_in(DofBus, GyroAddr, 0x00, 1, (unsigned char*)reg_in, 1);
print("ID readback: 0x%x\n\n", reg_in[0]);
break;
case 3: //see ITG3200 data sheet
reg_out[0] = 0x01; //Power control: Set clk to xGyro, all gyros on
i2c_out(DofBus, GyroAddr, 0x3E, 1, (unsigned char*)reg_out, 1);
i2c_in(DofBus, GyroAddr, 0x3E, 1, (unsigned char*)reg_in, 1);
print("Power control: 0x%x\n", reg_in[0]);
reg_out[0] = 0x09; //Sample rate divider: set to 9, gives x/10 = sample output rate, where x is internal rate
i2c_out(DofBus, GyroAddr, 0x15, 1, (unsigned char*)reg_out, 1);
i2c_in(DofBus, GyroAddr, 0x15, 1, (unsigned char*)reg_in, 1);
print("Rate divider: 0x%x\n", reg_in[0]);
reg_out[0] = 0x1A; //scale selection and digital filter: bits 4&5: = 0b11: full scale. bits 2 10:
i2c_out(DofBus, GyroAddr, 0x16, 1, (unsigned char*)reg_out, 1);
i2c_in(DofBus, GyroAddr, 0x16, 1, (unsigned char*)reg_in, 1);
print("Digital Filter: 0x%x\n", reg_in[0]);
break;
case 4:
dt = CLKFREQ*5; // 5 second timeout
//CLKFREQ contains the number of ticks in one second, CNT returns current tick no
t = CNT; // Mark current time by storing in t
while(CNT - t < dt) // Repeat until timeout
{
i2c_in(DofBus, GyroAddr, 0x1D, 1, (unsigned char*)buffer, 6); //read 6 registers starting at 0x1D - data registers
x = twos2signed(buffer[0], buffer[1]) - xGyroDrift; //convert 2s compliment split into 2 registers into signed
y = twos2signed(buffer[2], buffer[3]) - yGyroDrift; //and subtract gyro drift
z = twos2signed(buffer[4], buffer[5]) - zGyroDrift;
print("\nX: %d Y: %d Z: %d\n", x, y, z);
pause(500);
}
break;
case 5:
dt = CLKFREQ*30; // 30 second timeout
t = CNT; // Mark current time by storing in t
while(CNT - t < dt) // Repeat until timeout
{
i2c_in(DofBus, GyroAddr, 0x1D, 1, (unsigned char*)buffer, 6);
x = twos2signed(buffer[0], buffer[1]) - xGyroDrift;
y = twos2signed(buffer[2], buffer[3]) - yGyroDrift;
z = twos2signed(buffer[4], buffer[5]) - zGyroDrift;
print("\nX: %d Y: %d Z: %d\n", x, y, z);
pause(500);
}
break;
case 6:
tic = CNT;
dt = CLKFREQ/100; //100HZ cycle NB. integer math
xsum = 0;
ysum = 0;
zsum = 0;
for (int i = 0; i < 400; i++) // 4 seconds
{
t = CNT; // Mark current time by storing in t
i2c_in(DofBus, GyroAddr, 0x1D, 1, (unsigned char*)buffer, 6);
xsum += ((float)twos2signed(buffer[0], buffer[1])) / 400; //running 400 piece average
ysum += ((float)twos2signed(buffer[2], buffer[3])) / 400;
zsum += ((float)twos2signed(buffer[4], buffer[5])) / 400;
while(CNT - t < dt){}
}
print("\nelapsed time: %f\n", ((float)(CNT-tic))/CLKFREQ );
print("xdrift: %f, ydrift: %f, zdrift: %f\n", xsum, ysum, zsum);
break;
case 7:
//currently set up for y axis
//by taking the variance over a known total rotation (ie rotating exactly 90 degrees, and reading 93 degrees)
//a variance in the Gyro scaling factor can be estimated as (93-90)/90 = 3.33%
//print("\nGyro conversion factor: %f\n", GyroConv);
dt = CLKFREQ/100; //200HZ cycle NB integer math here
prev = 0;
current = 0;
sum = 0;
//aqquire first sample
t = CNT; // Mark current time by storing in t
i2c_in(DofBus, GyroAddr, 0x1D, 1, (unsigned char*)buffer, 6);
prev= ( (float)twos2signed(buffer[2], buffer[3]) -yGyroDrift) * yGyroConv;
while(CNT - t < dt);
//calculate angle over time by taking consecutive values, and using tustins approximation to integration (check name?)
//sum this angle over consecutive points
for (int i = 0; i < 1000; i++) // 1000 samples/100HZ = 10 seconds.
{
t = CNT; // Mark current time by storing in t
i2c_in(DofBus, GyroAddr, 0x1D, 1, (unsigned char*)buffer, 6);
current= ( (float)twos2signed(buffer[2], buffer[3]) -yGyroDrift) * yGyroConv;
sum += (current +prev) * 0.01/2; //Tustins approximation to integration
prev = current;
while(CNT - t < dt){}
}
print("\nFinal Rotation: %f\n", sum);
break;
case 8:
//debugging case - replace code with whatever suits
print("\n\nCLKFREQ: %d\n", CLKFREQ);
tic = CNT;
dt = CLKFREQ/2; //2HZ cycle NB. integer math
sum = 0;
for (int i = 0; i < 10; i++) // 5 seconds
{
t = CNT; // Mark current time by storing in t
pause(1);
//print("Reading: %f sum: %f\n", temp, sum);
while(CNT - t < dt){}
}
print("\nCNT-tic: %d\n", CNT-tic);
print("elapsed time: %f\n", ((float)(CNT-tic))/CLKFREQ );
break;
default:
//code
break;
}
}
}
/**
* @brief Interrupt service routine for i2c-1
* @param[in] None
* @return None
*/
static void i2c1ISR(void)
{
int32_t csr, val;
i2c_dev *dev;
dev = (i2c_dev *) ( (uint32_t)&i2c_device[1] );
csr = i2c_in(dev, I2C_CSR);
csr |= 0x04;
i2c_out(dev, csr, I2C_CSR); /* clear interrupt flag */
if(dev->state == I2C_STATE_NOP)
return;
if((csr & 0x800) && bNackValid) /* NACK only valid in WRITE */
{
dev->last_error = I2C_ERR_NACK;
_i2cCommand(dev, I2C_CMD_STOP);
dev->state = I2C_STATE_NOP;
}
else if(csr & 0x200) /* Arbitration lost */
{
sysprintf("Arbitration lost\n");
dev->last_error = I2C_ERR_LOSTARBITRATION;
dev->state = I2C_STATE_NOP;
}
else if(!(csr & 0x100)) /* transmit complete */
{
if(dev->pos < dev->subaddr_len + 1) /* send address state */
{
val = dev->buffer[dev->pos++] & 0xff;
i2c_out(dev, val, I2C_TxR);
_i2cCommand(dev, I2C_CMD_WRITE);
}
else if(dev->state == I2C_STATE_READ)
{
/* sub address send over , begin restart a read command */
if(dev->pos == dev->subaddr_len + 1)
{
val = dev->buffer[dev->pos++];
i2c_out(dev, val, I2C_TxR);
_i2cCommand(dev, I2C_CMD_START | I2C_CMD_WRITE);
}
else
{
dev->buffer[dev->pos++] = i2c_in(dev, I2C_RxR) & 0xff;
if( dev->pos < dev->len)
{
if(dev->pos == dev->len -1 ) /* last character */
_i2cCommand(dev, I2C_CMD_READ |
I2C_CMD_STOP |
I2C_CMD_NACK);
else
_i2cCommand(dev, I2C_CMD_READ);
}
else
{
dev->state = I2C_STATE_NOP;
}
}
}
else if(dev->state == I2C_STATE_WRITE) /* write data */
{
if( dev->pos < dev->len)
{
val = dev->buffer[dev->pos];
i2c_out(dev, val, I2C_TxR);
if(dev->pos == dev->len -1 ) /* last character */
_i2cCommand(dev, I2C_CMD_WRITE| I2C_CMD_STOP);
else
_i2cCommand(dev, I2C_CMD_WRITE);
dev->pos ++;
}
else
{
dev->state = I2C_STATE_NOP;
}
}
}
}
