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CAN Message Utilities for C
============
## Bitfield Manipulation
uint8_t data[4] = {0x12, 0x34, 0x56, 0x78};
uint8_t result = getByte(data, sizeof(data), 0);
uint8_t result = getNibble(data, sizeof(data), 0);
fail_unless(copyBitsRightAligned(data, 4, 4, 12, result, 4));
## 8 Byte Bitfield Manipulation
TODO setting bit fields is just copying
TODO bring back old uint64_t implementation of getBitField if it's faster /
simpler
## CAN Signal Encoding
The library supports encoding floating point CAN signals as well as booleans
into a uint64_t payload.
uint64_t payload = bitfield_encode_float(1, 1, 3, 1, 0)
// payload == 0x1000000000000000
payload = bitfield_encode_bool(true, 1, 3);
// payload == 0x1000000000000000
## CAN Signal Decoding
The library supports parsing floating point CAN signals as well as booleans.
uint64_t payload = 0xeb00000000000000;
float float_result = bitfield_parse_float(payload,
2, // starting bit
4, // width of the signal's field
1001.0, // transformation factor for the signal value
-30000.0); // transformation offset for the signal value
// float_result == -19990.0
bool bool_result = bitfield_parse_bool(payload,
0, // starting bit
1, // width of the signal's field
1.0, // transformation factor for the signal value
0); // transformation offset for the signal value
// bool_result == true
## Testing
The library includes a test suite that uses the `check` C unit test library.
$ make test
## Authors
Chris Peplin cpeplin@ford.com
## License
Copyright (c) 2013 Ford Motor Company
Licensed under the BSD license.
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