Steven Kay
/
MCP9803_NUCLEO_Driver
Initial I2C Working
Diff: MCP9803/MCP9803.cpp
- Revision:
- 2:832cb4376d2a
- Parent:
- 1:444546e8cd20
diff -r 444546e8cd20 -r 832cb4376d2a MCP9803/MCP9803.cpp --- a/MCP9803/MCP9803.cpp Wed Mar 29 12:20:34 2017 +0000 +++ b/MCP9803/MCP9803.cpp Wed Mar 29 17:55:38 2017 +0000 @@ -30,26 +30,115 @@ inBuffer = (char *)malloc(1); } -int MCP9803::ConfigSensor() + + +int MCP9803::ConfigSensor( int shutdown, int comp_int, int alert_polarity, + int fault_guide, int adc_res, int one_shot) { + // Assign passed values to struct members + CONFIG_REG_VALUE.CONFIG_BITS.SHUTDOWN_BIT = shutdown; + CONFIG_REG_VALUE.CONFIG_BITS.COMP_INT_BIT = comp_int; + CONFIG_REG_VALUE.CONFIG_BITS.ALERT_POLARITY_BIT = alert_polarity; + CONFIG_REG_VALUE.CONFIG_BITS.FAULT_QUEUE = fault_guide; + CONFIG_REG_VALUE.CONFIG_BITS.ADC_RES = adc_res; + CONFIG_REG_VALUE.CONFIG_BITS.ONE_SHOT = one_shot; + + // Generate Command to send to MCP9803 + // <Pointer to Config Register, CONFIG Register Value> + char dataOut[] = {CONFIG_REG_POINT, CONFIG_REG_VALUE.CONFIG_VALUE}; + + // Write Bytes to MCP9803 + int writeReturn = I2C_Write(dataOut,CONFIG_CMD_LENGTH); + + // Check on return status of the Write command + if(writeReturn != 0) + { + // Failure + return FAILURE; + } + else + { + // Success + return SUCCESS; + } +} + + +int MCP9803::RawTempValue() +{ + // Set MCP9803 Register Pointer to point to Temperature Register + I2C_Write((char *)TEMP_REG_POINT,1); + + // Read TEMP_DATA_LENGTH bytes into temp buffer + char *tempInBuffer = I2C_Read(TEMP_DATA_LENGTH); + // Convert tempInBuffer to rawData + // Shift first Byte (MSB) up by 8, OR with second Byte (LSB) + // Then shift Result down by 4 + int rawData = ((*(tempInBuffer)<<8|*(tempInBuffer+1))>>4); + + // + return rawData; +} + + + +float MCP9803::FormattedTempValue(int format) +{ + // Get Raw Temp Value + int tempData = RawTempValue(); - return 0; + if(tempData == READ_TEMP_FAIL_VALUE) + { + return READ_TEMP_FAIL_ERROR; + } + + // Check and convert if 2's Complement + if(tempData > 2047) + { + tempData -= 4096; + } + + // Return formatted data based on format + switch(format) + { + // Return celcius value of temperature + case CELCIUS: + return (RAW_TO_C*tempData); + + // Return farenheit value of temperature + case FARENHEIT: + return ((RAW_TO_C*tempData)*C_F_1)+C_F_2; + + // Return Kelvin value of temperature + case KELVIN: + return ((RAW_TO_C*tempData)+C_TO_F); + + // If input is invalid, return value outwith range + // of other format options + default: + return FORMAT_FAIL; + } } int MCP9803::I2C_Write(char *dataOut,int dataLen) { + // Define Char Buffer of length dataLen char outBuffer[dataLen]; + // Populate Buffer with dataOut for(int i=0 ; i<dataLen ; i++) { outBuffer[i] = *(dataOut+i); } + // Write out to I2C Bus int sendStatus = _I2C -> write(chipAddress,outBuffer,dataLen,0); + // Return success value of the Write + // Returns 0 for Success, 1 for failure return sendStatus; } @@ -57,50 +146,47 @@ char *MCP9803::I2C_Read(int dataLen) { + // Reallocate memory to dataLen length expected for inBuffer setBufferSize(dataLen); + // Read from the I2C Bus int receiveStatus = _I2C -> read(chipAddress,inBuffer,dataLen,0); + // Check success value + // If receiveStatus != 0, indicates failure if(receiveStatus != 0) { + // Generate unique command to indicate failure, based on number of + // expected incoming bytes for(int i = 0; i < dataLen; i++) { + // For even indexes of inBuffer if(i % 2 == 0) { - inBuffer[i] = 0xFF; + inBuffer[i] = FAIL_EVEN_VALUE; } + // For odd indexes of inBuffer else { - inBuffer[i] = 0x00; + inBuffer[i] = FAIL_ODD_VALUE; } - printf("Buffer Value = %02x",inBuffer[i]); } + // Return unique error command return inBuffer; } - else { + // Return Buffer contents based on successful read return inBuffer; } - } void MCP9803::setBufferSize(int dataLen) { + // Reallocate memory for the inBuffer to account for differing lengths of + // data which can be read in inBuffer = (char *)realloc(inBuffer, dataLen); } - -char *MCP9803::getBuffer() -{ - -} - -void MCP9803::setBuffer() -{ - -} - - /********************************************************************************************