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Diffstat (limited to 'CAN-binder/libs/nanopb/examples/using_double_on_avr/README.txt')
| -rw-r--r-- | CAN-binder/libs/nanopb/examples/using_double_on_avr/README.txt | 25 |
1 files changed, 0 insertions, 25 deletions
diff --git a/CAN-binder/libs/nanopb/examples/using_double_on_avr/README.txt b/CAN-binder/libs/nanopb/examples/using_double_on_avr/README.txt deleted file mode 100644 index d9fcdfc..0000000 --- a/CAN-binder/libs/nanopb/examples/using_double_on_avr/README.txt +++ /dev/null @@ -1,25 +0,0 @@ -Nanopb example "using_double_on_avr" -==================================== - -Some processors/compilers, such as AVR-GCC, do not support the double -datatype. Instead, they have sizeof(double) == 4. Because protocol -binary format uses the double encoding directly, this causes trouble -if the protocol in .proto requires double fields. - -This directory contains a solution to this problem. It uses uint64_t -to store the raw wire values, because its size is correct on all -platforms. The file double_conversion.c provides functions that -convert these values to/from floats, without relying on compiler -support. - -To use this method, you need to make some modifications to your code: - -1) Change all 'double' fields into 'fixed64' in the .proto. - -2) Whenever writing to a 'double' field, use float_to_double(). - -3) Whenever reading a 'double' field, use double_to_float(). - -The conversion routines are as accurate as the float datatype can -be. Furthermore, they should handle all special values (NaN, inf, denormalized -numbers) correctly. There are testcases in test_conversions.c. |