uint8_t i2c_endTransmission(uint8_t stop) { // actually sends the buffer
bool xferOK = false;
uint8_t errorCode = 0;
xferOK = USI_TWI_Start_Read_Write(USI_Buf,USI_BufIdx+1); // core func that does the work
USI_BufIdx = 0;
if (xferOK) {
if (stop) {
errorCode = USI_TWI_Master_Stop();
if (errorCode == 0) {
errorCode = USI_TWI_Get_State_Info();
return errorCode;
}
}
return 0;
} else { // there was an error
errorCode = USI_TWI_Get_State_Info(); // this function returns the error number
return errorCode;
}
}
//read value of channel 1 of the light sensor
uint16_t read_ch1(){
unsigned char message[2];
message[0] = 0x9E;
I2C_write(LIGHT_SENSOR_ADDR, message, 1, FALSE);
do{
I2C_read(LIGHT_SENSOR_ADDR, message, 2, TRUE);
} while(USI_TWI_Get_State_Info() == USI_TWI_NO_ACK_ON_ADDRESS);
return (*((uint16_t*)message));
}
uint8_t USI_TWI::endTransmission(){ // actually sends the buffer
bool xferOK = false;
uint8_t errorCode = 0;
xferOK = USI_TWI_Start_Read_Write(USI_Buf,USI_BufIdx+1); // core func that does the work
USI_BufIdx = 0;
if (xferOK) return 0;
else { // there was an error
errorCode = USI_TWI_Get_State_Info(); // this function returns the error number
return errorCode;
}
}
uint8_t i2c_requestFrom(uint8_t slaveAddr, uint8_t numBytes){ // setup for receiving from slave
bool xferOK = false;
uint8_t errorCode = 0;
USI_LastRead = 0;
USI_BytesAvail = numBytes; // save this off in a global
numBytes++; // add extra byte to transmit header
USI_Buf[0] = (slaveAddr<<TWI_ADR_BITS) | USI_RCVE; // setup address & Rcve bit
xferOK = USI_TWI_Start_Read_Write(USI_Buf,numBytes); // core func that does the work
// USI_Buf now holds the data read
if (xferOK) {
errorCode = USI_TWI_Master_Stop();
if (errorCode == 0) {
errorCode = USI_TWI_Get_State_Info();
return errorCode;
}
return 0;
} else { // there was an error
errorCode = USI_TWI_Get_State_Info(); // this function returns the error number
return errorCode;
}
}
static unsigned int display_number(unsigned int n) {
unsigned char data[2];
unsigned int digit_1 = 0;
unsigned int digit_2 = 0;
if(n > 99)
n = 99;
digit_1 = n % 10;
digit_2 = n / 10;
if (digit_2 == 8) digit_2 = 9;
else if (digit_2 == 9) digit_2 = 8;
data[0] = PCF8574_ADDRESS << 1;
data[1] = (digit_1 << 4) | (digit_2);
USI_TWI_Start_Transceiver_With_Data(data, 2);
return USI_TWI_Get_State_Info();
}
int16_t I2C_masterReadRegisterByte(I2C_Device *dev, uint8_t *reg, uint8_t rLen, uint8_t *data, uint8_t dLen) {
#ifdef USI_TWI
uint8_t cmd_buf[MAX_REQ_BUF]; // For speed reasons, use a static buffer...
if (dLen +rLen >= MAX_REQ_BUF) dLen = MAX_REQ_BUF - (rLen + 1);
cmd_buf[0] = (((dev->id << 4) & 0xF0) | ((dev->address << 1) & 0x0E)) | (FALSE << TWI_READ_BIT);
for (int curReg = 0; curReg < rLen; curReg++) {
cmd_buf[1 + curReg] = reg[curReg];
}
int retval = USI_TWI_Start_Transceiver_With_Data(cmd_buf, 1 + rLen);
if (retval != TRUE) return -1;
cmd_buf[0] = (((dev->id << 4) & 0xF0) | ((dev->address << 1) & 0x0E)) | (TRUE << TWI_READ_BIT);
do {
retval = USI_TWI_Start_Transceiver_With_Data(cmd_buf, 1 + dLen);
} while(USI_TWI_Get_State_Info() == USI_TWI_NO_ACK_ON_ADDRESS);
for (uint8_t bufIdx = 0; bufIdx < dLen; bufIdx++)
data[bufIdx] = cmd_buf[bufIdx + 1];
return (retval == TRUE) ? dLen : -1;
#else
uint8_t twiStatus;
uint8_t retryCount = 0;
int16_t retval = dLen;
while (retryCount < MAX_RETRIES) {
// Start command
twiStatus = I2C_internal_sendCommand(I2C_StartCommand);
if (twiStatus == TW_MT_ARB_LOST) { // We need to retry...
retryCount++;
continue; // Begin to loop again
} else if ((twiStatus != TW_START) && (twiStatus != TW_REP_START)) {
retval = -1;
break;
}
// Now send slave address... asking for a write
TWDR = ((dev->id << 4) & 0xF0) | ((dev->address << 1) & 0x0E) | TW_WRITE;
twiStatus = I2C_internal_sendCommand(I2C_DataNACKCommand);
if ((twiStatus == TW_MT_SLA_NACK) || (twiStatus == TW_MT_ARB_LOST)) {
retryCount++;
continue;
} else if (twiStatus != TW_MT_SLA_ACK) {
retval = -1;
break;
}
// Send register address
for (int curReg = 0; curReg < rLen; curReg++) {
TWDR = reg[curReg];
twiStatus = I2C_internal_sendCommand(I2C_DataNACKCommand);
if (twiStatus != TW_MT_DATA_ACK) {
retval = -1;
break;
}
}
if (retval == -1) break; // Something bad happened sending the register address
// Send start command again.
twiStatus = I2C_internal_sendCommand(I2C_StartCommand);
if (twiStatus == TW_MT_ARB_LOST) { // We need to retry...
retryCount++;
continue; // Begin to loop again
} else if ((twiStatus != TW_START) && (twiStatus != TW_REP_START)) {
retval = -1;
break;
}
// Now send slave address... asking for a read
TWDR = ((dev->id << 4) & 0xF0) | ((dev->address << 1) & 0x0E) | TW_READ;
twiStatus = I2C_internal_sendCommand(I2C_DataNACKCommand);
if ((twiStatus == TW_MR_SLA_NACK) || (twiStatus == TW_MR_ARB_LOST)) {
retryCount++;
continue;
} else if (twiStatus != TW_MR_SLA_ACK) {
retval = -1;
break;
}
for (int curData = 0; curData < dLen; curData++) {
// Read the data
if (curData == (dLen - 1)) { // Last read... we need to send a NACK
twiStatus = I2C_internal_sendCommand(I2C_DataNACKCommand);
if (twiStatus != TW_MR_DATA_NACK) {
retval = -1;
break;
}
} else { // We have to perform other reads... send an ACK
twiStatus = I2C_internal_sendCommand(I2C_DataACKCommand);
if (twiStatus != TW_MR_DATA_ACK) {
retval = -1;
break;
}
}
// Read the data!
data[curData] = TWDR;
}
break;
}
twiStatus = I2C_internal_sendCommand(I2C_StopCommand);
return retval;
#endif
}
