Library for reading temperature from DS1820, DS18B20 and DS1822
Dependents: heatmap BLE_Temperature BLE_Temperature_Exercise F334andDS18B20 ... more
Fork of DS1820 by
HelloWorld: http://mbed.org/users/Sissors/code/DS1820_HelloWorld/
Library should currently work on all mbed targets, let me know if there is an issue. First however make sure you have latest version of mbed library and this library.
Diff: DS1820.cpp
- Revision:
- 11:1a3c3002b50c
- Parent:
- 10:d297ce9ce422
- Child:
- 12:196e9e54b033
--- a/DS1820.cpp Fri Jan 30 11:07:10 2015 +0000 +++ b/DS1820.cpp Mon Feb 16 16:53:11 2015 +0000 @@ -213,53 +213,53 @@ } bool DS1820::ROM_checksum_error(char *_ROM_address) { - char CRC=0x00; + char _CRC=0x00; int i; for(i=0;i<7;i++) // Only going to shift the lower 7 bytes - CRC = CRC_byte(CRC, _ROM_address[i]); + _CRC = CRC_byte(_CRC, _ROM_address[i]); // After 7 bytes CRC should equal the 8th byte (ROM CRC) - return (CRC!=_ROM_address[7]); // will return true if there is a CRC checksum mis-match + return (_CRC!=_ROM_address[7]); // will return true if there is a CRC checksum mis-match } bool DS1820::RAM_checksum_error() { - char CRC=0x00; + char _CRC=0x00; int i; for(i=0;i<8;i++) // Only going to shift the lower 8 bytes - CRC = CRC_byte(CRC, RAM[i]); + _CRC = CRC_byte(_CRC, RAM[i]); // After 8 bytes CRC should equal the 9th byte (RAM CRC) - return (CRC!=RAM[8]); // will return true if there is a CRC checksum mis-match + return (_CRC!=RAM[8]); // will return true if there is a CRC checksum mis-match } -char DS1820::CRC_byte (char CRC, char byte ) { +char DS1820::CRC_byte (char _CRC, char byte ) { int j; for(j=0;j<8;j++) { - if ((byte & 0x01 ) ^ (CRC & 0x01)) { + if ((byte & 0x01 ) ^ (_CRC & 0x01)) { // DATA ^ LSB CRC = 1 - CRC = CRC>>1; + _CRC = _CRC>>1; // Set the MSB to 1 - CRC = CRC | 0x80; + _CRC = _CRC | 0x80; // Check bit 3 - if (CRC & 0x04) { - CRC = CRC & 0xFB; // Bit 3 is set, so clear it + if (_CRC & 0x04) { + _CRC = _CRC & 0xFB; // Bit 3 is set, so clear it } else { - CRC = CRC | 0x04; // Bit 3 is clear, so set it + _CRC = _CRC | 0x04; // Bit 3 is clear, so set it } // Check bit 4 - if (CRC & 0x08) { - CRC = CRC & 0xF7; // Bit 4 is set, so clear it + if (_CRC & 0x08) { + _CRC = _CRC & 0xF7; // Bit 4 is set, so clear it } else { - CRC = CRC | 0x08; // Bit 4 is clear, so set it + _CRC = _CRC | 0x08; // Bit 4 is clear, so set it } } else { // DATA ^ LSB CRC = 0 - CRC = CRC>>1; + _CRC = _CRC>>1; // clear MSB - CRC = CRC & 0x7F; + _CRC = _CRC & 0x7F; // No need to check bits, with DATA ^ LSB CRC = 0, they will remain unchanged } byte = byte>>1; } -return CRC; +return _CRC; } int DS1820::convertTemperature(bool wait, devices device) { @@ -361,16 +361,16 @@ } answer = reading +0.0; // convert to floating point if ((FAMILY_CODE == FAMILY_CODE_DS18B20 ) || (FAMILY_CODE == FAMILY_CODE_DS1822 )) { - answer = answer / 16.0; + answer = answer / 16.0f; } else { remaining_count = RAM[6]; count_per_degree = RAM[7]; - answer = floor(answer/2.0) - 0.25 + (count_per_degree - remaining_count) / count_per_degree; + answer = floor(answer/2.0f) - 0.25f + (count_per_degree - remaining_count) / count_per_degree; } if (scale=='F' or scale=='f') // Convert to deg F - answer = answer * 9.0 / 5.0 + 32.0; + answer = answer * 9.0f / 5.0f + 32.0f; } return answer; }