Question

Waveform Generation Calculate the wavetable (data array) of the digital sine wave if 20 samples from an 8 bit DAC are used to represent one cycle and offset by 1/2 of the maximum amplitude. Determine your wavetable as two arrays, one positive going and one negative going. Decimal Sample Binary Sample Hex Sample 10 12 20 char PosCycle[] { char NegCycle[] = {

Answer 1

Hello,
          Please find the answer attached as under. Please give a thumbs up rating if you find the answer useful! Have a rocking day ahead!

Here, we have one half of a sine wave being represented by 20 samples. The samples are further digitized by a 8 bit DAC. Also, the sine wave is offset by half of the max amplitude. Let the max amplitude be 1. Thus, the sine wave will be of the form 0.5 + sin(wt). Since the frequency is not provided, we assume frequency to be 1 Hz. Thus, the decimal, binary and the hex sample are noted here:

n	Decimal	Binary	Hex
1	0.5	0     1     0     0     1     1     0     0	32
2	0.6564	0     1     0     0     0     0     1     0	42
3	0.809	1     0     0     0     1     0     1     0	51
4	0.95	1     1     1     1     1     0     1     0	5F
5	1.0878	1     0     1     1     0     1     1     0	6D
6	1.2071	1     0     0     1     1     1     1     0	79
7	1.3090	1     1     0     0     0     0     0     1	83
8	1.3910	1     1     0     1     0     0     0     1	8B
9	1.4511	1     0     0     0     1     0     0     1	91
10	1.4877	1     0     1     0     1     0     0     1	95
11	1.5	0     1     1     0     1     0     0     1	96
12	1.4877	1     0     1     0     1     0     0     1	95
13	1.4511	1     0     0     0     1     0     0     1	91
14	1.3910	1     1     0     1     0     0     0     1	8B
15	1.3090	1     1     0     0     0     0     0     1	83
16	1.2071	1     0     0     1     1     1     1     0	79
17	1.0878	1     0     1     1     0     1     1     0	6D
18	0.9540	1     1     1     1     1     0     1     0	5F
19	0.8090	1     0     0     0     1     0     1     0	51

20      0.6564             0     1     0     0     0     0     1     0                                        42

Note: There was an error in the table with 20 rows, hence had to put the last row outside the table.

*****************************************************************
PS: Please do not forget the thumbs up