1 /* AVR-GCC does not have real double datatype. Instead its double 2 * is equal to float, i.e. 32 bit value. If you need to communicate 3 * with other systems that use double in their .proto files, you 4 * need to do some conversion. 5 * 6 * These functions use bitwise operations to mangle floats into doubles 7 * and then store them in uint64_t datatype. 8 */ 9 10 #ifndef DOUBLE_CONVERSION 11 #define DOUBLE_CONVERSION 12 13 #include <stdint.h> 14 15 /* Convert native 4-byte float into a 8-byte double. */ 16 extern uint64_t float_to_double(float value); 17 18 /* Convert 8-byte double into native 4-byte float. 19 * Values are rounded to nearest, 0.5 away from zero. 20 * Overflowing values are converted to Inf or -Inf. 21 */ 22 extern float double_to_float(uint64_t value); 23 24 25 #endif 26 27
