Luke Cartwright / Mbed 2 deprecated ELEC2645_Project_el18loc_nearlythere

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Dependencies:   mbed

LUTs/LUTS.cpp@9:f6ba53e355a0, 2020-05-06 (annotated)

Committer:
lukeocarwright
Date:
Wed May 06 14:37:34 2020 +0000
Revision:
9:f6ba53e355a0
Parent:
7:33cb5f2db1ee
Child:
10:258a1eca02cc
Outputted sin LUT in uint16_t with unit test using DEBUG macro. Allows direct writing of value to table to 16-bit DAC.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
lukeocarwright 7:33cb5f2db1ee 1 #include "mbed.h"
lukeocarwright 7:33cb5f2db1ee 2 #include "LUTs.h"
lukeocarwright 7:33cb5f2db1ee 3
lukeocarwright 7:33cb5f2db1ee 4 LUTs::LUTs()
lukeocarwright 7:33cb5f2db1ee 5 {
lukeocarwright 7:33cb5f2db1ee 6 }
lukeocarwright 7:33cb5f2db1ee 7 LUTs::~LUTs()
lukeocarwright 7:33cb5f2db1ee 8 {
lukeocarwright 7:33cb5f2db1ee 9 }
lukeocarwright 9:f6ba53e355a0 10 volatile uint16_t sin_wavtable[1024];
lukeocarwright 7:33cb5f2db1ee 11
lukeocarwright 7:33cb5f2db1ee 12 void LUTs::sin_wavetable()
lukeocarwright 7:33cb5f2db1ee 13 {
lukeocarwright 7:33cb5f2db1ee 14 printf("Generating Wavetable \n");
lukeocarwright 9:f6ba53e355a0 15 for (int i=0; i<1024; i++) {
lukeocarwright 9:f6ba53e355a0 16 sin_d= 65535*(0.5*sin(2.0*PI*(i/1024.0))+0.5);
lukeocarwright 9:f6ba53e355a0 17 //calculates remainder for rounding
lukeocarwright 9:f6ba53e355a0 18 rem= fmod(sin_d,1);
lukeocarwright 9:f6ba53e355a0 19 //printf("preround= %g -", sin_d); //DEBUG
lukeocarwright 9:f6ba53e355a0 20 if (rem>=0.5) {
lukeocarwright 9:f6ba53e355a0 21 sin_d=ceil(sin_d); //round UP
lukeocarwright 9:f6ba53e355a0 22 } else {
lukeocarwright 9:f6ba53e355a0 23 sin_d= floor(sin_d-rem); //round DOWN
lukeocarwright 9:f6ba53e355a0 24 }
lukeocarwright 9:f6ba53e355a0 25 // printf("Postround= %g -",sin_d); //DEBUG
lukeocarwright 9:f6ba53e355a0 26 sin_u=((uint16_t)sin_d);
lukeocarwright 9:f6ba53e355a0 27 //printf("sin_u= %u \n", sin_u);
lukeocarwright 9:f6ba53e355a0 28 sin_wavtable[i]=sin_u;
lukeocarwright 9:f6ba53e355a0 29 //sin_wavtable[i]=get_sin(i);
lukeocarwright 9:f6ba53e355a0 30 }
lukeocarwright 9:f6ba53e355a0 31 /*//DEBUG
lukeocarwright 9:f6ba53e355a0 32 for (int i=0; i<1024; i=i+128) {
lukeocarwright 9:f6ba53e355a0 33 printf("sin_wav[%d]= %u \n", i, sin_wavtable);
lukeocarwright 7:33cb5f2db1ee 34 }
lukeocarwright 9:f6ba53e355a0 35 */
lukeocarwright 9:f6ba53e355a0 36 }
lukeocarwright 9:f6ba53e355a0 37
lukeocarwright 9:f6ba53e355a0 38
lukeocarwright 9:f6ba53e355a0 39
lukeocarwright 9:f6ba53e355a0 40
lukeocarwright 9:f6ba53e355a0 41
lukeocarwright 9:f6ba53e355a0 42 /*
lukeocarwright 9:f6ba53e355a0 43 uint16_t get_sin(int i)
lukeocarwright 9:f6ba53e355a0 44 {
lukeocarwright 9:f6ba53e355a0 45 //calculates sin val as double (0->65535)
lukeocarwright 9:f6ba53e355a0 46
lukeocarwright 9:f6ba53e355a0 47 sin_d= 65535*(0.5*sin(2.0*PI*(i/1024.0))+0.5);
lukeocarwright 9:f6ba53e355a0 48 //calculates remainder for rounding
lukeocarwright 9:f6ba53e355a0 49 rem= fmod(sin_d,1);
lukeocarwright 9:f6ba53e355a0 50 //printf("preround= %g -", sin_d[i]); //DEBUG
lukeocarwright 9:f6ba53e355a0 51 if (rem>=0.5) {
lukeocarwright 9:f6ba53e355a0 52 sin_d=ceil(sin_d); //round UP
lukeocarwright 9:f6ba53e355a0 53 } else {
lukeocarwright 9:f6ba53e355a0 54 sin_d= floor(sin_d-rem); //round DOWN
lukeocarwright 9:f6ba53e355a0 55 }
lukeocarwright 9:f6ba53e355a0 56 //printf("Postround= %g -",sin_d[i]); //DEBUG
lukeocarwright 9:f6ba53e355a0 57 return((uint16_t)sin_d);
lukeocarwright 9:f6ba53e355a0 58
lukeocarwright 9:f6ba53e355a0 59 //summed into one function
lukeocarwright 9:f6ba53e355a0 60 return((uint16_t)floor(65535*(0.5*sin(2.0*PI*(i/1024.0))+0.5)));
lukeocarwright 9:f6ba53e355a0 61 }
lukeocarwright 9:f6ba53e355a0 62 */