1-Wire® library for mbed. Complete 1-Wire library that supports our silicon masters along with a bit-bang master on the MAX32600MBED platform with one common interface for mbed. Slave support has also been included and more slaves will be added as time permits.
Dependents: MAXREFDES131_Qt_Demo MAX32630FTHR_iButton_uSD_Logger MAX32630FTHR_DS18B20_uSD_Logger MAXREFDES130_131_Demo ... more
Superseded by MaximInterface.
crc.cpp@80:83b0d879cc32, 2016-06-02 (annotated)
- Committer:
- j3
- Date:
- Thu Jun 02 21:56:16 2016 +0000
- Revision:
- 80:83b0d879cc32
- Parent:
- 78:0cbbac7f2016
added support for DS1920 temperature i-button
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
j3 | 80:83b0d879cc32 | 1 | |
j3 | 80:83b0d879cc32 | 2 | |
IanBenzMaxim | 78:0cbbac7f2016 | 3 | #include "crc.h" |
IanBenzMaxim | 78:0cbbac7f2016 | 4 | |
j3 | 80:83b0d879cc32 | 5 | |
j3 | 80:83b0d879cc32 | 6 | uint8_t OneWire::crc::calculateCrc8(uint8_t crc8, uint8_t data) |
j3 | 80:83b0d879cc32 | 7 | { |
j3 | 80:83b0d879cc32 | 8 | // See Application Note 27 |
j3 | 80:83b0d879cc32 | 9 | crc8 = crc8 ^ data; |
j3 | 80:83b0d879cc32 | 10 | for (int i = 0; i < 8; i++) |
j3 | 80:83b0d879cc32 | 11 | { |
j3 | 80:83b0d879cc32 | 12 | if (crc8 & 1) |
j3 | 80:83b0d879cc32 | 13 | { |
j3 | 80:83b0d879cc32 | 14 | crc8 = (crc8 >> 1) ^ 0x8c; |
j3 | 80:83b0d879cc32 | 15 | } |
j3 | 80:83b0d879cc32 | 16 | else |
j3 | 80:83b0d879cc32 | 17 | { |
j3 | 80:83b0d879cc32 | 18 | crc8 = (crc8 >> 1); |
j3 | 80:83b0d879cc32 | 19 | } |
j3 | 80:83b0d879cc32 | 20 | } |
j3 | 80:83b0d879cc32 | 21 | |
j3 | 80:83b0d879cc32 | 22 | return crc8; |
j3 | 80:83b0d879cc32 | 23 | } |
j3 | 80:83b0d879cc32 | 24 | |
j3 | 80:83b0d879cc32 | 25 | uint8_t OneWire::crc::calculateCrc8(const uint8_t * data, size_t dataLen, uint8_t crc) |
j3 | 80:83b0d879cc32 | 26 | { |
j3 | 80:83b0d879cc32 | 27 | for (size_t i = 0; i < dataLen; i++) |
j3 | 80:83b0d879cc32 | 28 | { |
j3 | 80:83b0d879cc32 | 29 | crc = calculateCrc8(crc, data[i]); |
j3 | 80:83b0d879cc32 | 30 | } |
j3 | 80:83b0d879cc32 | 31 | return crc; |
j3 | 80:83b0d879cc32 | 32 | } |
j3 | 80:83b0d879cc32 | 33 | |
IanBenzMaxim | 78:0cbbac7f2016 | 34 | uint16_t OneWire::crc::calculateCrc16(uint16_t crc16, uint16_t data) |
IanBenzMaxim | 78:0cbbac7f2016 | 35 | { |
IanBenzMaxim | 78:0cbbac7f2016 | 36 | const uint16_t oddparity[] = { 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0 }; |
IanBenzMaxim | 78:0cbbac7f2016 | 37 | |
IanBenzMaxim | 78:0cbbac7f2016 | 38 | data = (data ^ (crc16 & 0xff)) & 0xff; |
IanBenzMaxim | 78:0cbbac7f2016 | 39 | crc16 >>= 8; |
IanBenzMaxim | 78:0cbbac7f2016 | 40 | |
IanBenzMaxim | 78:0cbbac7f2016 | 41 | if (oddparity[data & 0xf] ^ oddparity[data >> 4]) |
IanBenzMaxim | 78:0cbbac7f2016 | 42 | { |
IanBenzMaxim | 78:0cbbac7f2016 | 43 | crc16 ^= 0xc001; |
IanBenzMaxim | 78:0cbbac7f2016 | 44 | } |
IanBenzMaxim | 78:0cbbac7f2016 | 45 | |
IanBenzMaxim | 78:0cbbac7f2016 | 46 | data <<= 6; |
IanBenzMaxim | 78:0cbbac7f2016 | 47 | crc16 ^= data; |
IanBenzMaxim | 78:0cbbac7f2016 | 48 | data <<= 1; |
IanBenzMaxim | 78:0cbbac7f2016 | 49 | crc16 ^= data; |
IanBenzMaxim | 78:0cbbac7f2016 | 50 | |
IanBenzMaxim | 78:0cbbac7f2016 | 51 | return crc16; |
IanBenzMaxim | 78:0cbbac7f2016 | 52 | } |
IanBenzMaxim | 78:0cbbac7f2016 | 53 | |
IanBenzMaxim | 78:0cbbac7f2016 | 54 | uint16_t OneWire::crc::calculateCrc16(const uint8_t * data, size_t dataOffset, size_t dataLen, uint16_t crc) |
IanBenzMaxim | 78:0cbbac7f2016 | 55 | { |
IanBenzMaxim | 78:0cbbac7f2016 | 56 | for (size_t i = dataOffset; i < (dataLen + dataOffset); i++) |
IanBenzMaxim | 78:0cbbac7f2016 | 57 | { |
IanBenzMaxim | 78:0cbbac7f2016 | 58 | crc = calculateCrc16(crc, data[i]); |
IanBenzMaxim | 78:0cbbac7f2016 | 59 | } |
IanBenzMaxim | 78:0cbbac7f2016 | 60 | return crc; |
IanBenzMaxim | 78:0cbbac7f2016 | 61 | } |