sinwave.cpp

00001 /** sinwave class
00002  * Copyright (c) 2014, 2015 Motoo Tanaka @ Design Methodology Lab
00003  *
00004  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00005  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00006  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00007  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00008  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00009  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
00010  * THE SOFTWARE.
00011  */
00012 #include "sinwave.h"
00013 #include "sin_table.h"
00014 
00015 sinwave::sinwave(float v, int f, int d, int p) : wave(v, f, d, p) 
00016 {
00017     _name = "sin" ; 
00018 }
00019 
00020 sinwave::~sinwave(void) {}
00021 
00022 void sinwave::duty(int newvalue)
00023 {
00024     _duty = newvalue ;
00025 }
00026 
00027 int sinwave::duty(void) 
00028 {
00029     return( 50 ) ;
00030 }
00031 
00032 int sinwave::value(void)
00033 {
00034     int result = 0 ;
00035     
00036     if (_phase < 90) {
00037         result = _amp * (SIN_ZERO + sin_table[ _phase * NUM_SIN_TABLE / 90 ])/0xFFFF ;
00038     } else if (_phase < 180) {
00039         result = _amp * (SIN_ZERO + sin_table[(180 - _phase) * NUM_SIN_TABLE / 90])/0xFFFF ;
00040     } else if (_phase < 270) {
00041         result = _amp * (SIN_ZERO - sin_table[(_phase - 180) * NUM_SIN_TABLE / 90])/0xFFFF ;
00042     } else if (_phase < 360) {
00043         result = _amp * (SIN_ZERO - sin_table[(360 - _phase) * NUM_SIN_TABLE / 90])/0xFFFF ;
00044     }
00045     
00046     return( result ) ;
00047 }