/
main2.c
153 lines (124 loc) · 3.81 KB
/
main2.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
/*
* Antispy ultrasonic device for preventing voice recording
* with ultrasonic waves generation based on ATTINY85,
* ATTINY85 fuses have been set to internal PLL clock 16MHz
* with Resistor Ladder 5-bit Digital-to-Analog converter
* and piezzo-electric driver
* (C) Adam Loboda 2021, adam.loboda@wp.pl
*/
#include <stdint.h>
#include <util/delay.h>
#include <stdbool.h>
#include <avr/io.h>
#include <avr/pgmspace.h>
// PIN - PORT ASSIGNMENT DEFINITION FOR 5-BIT DAC DEVICE
#define OUTPUTPORT PORTB
#define OUTPUTPORTCTRL DDRB
// DEFINE 32 VALUES for ULTRASONIC WAVE SHAPE
// VIA 5-BIT Digital to Analog conversion
// saw like wave
/*const uint8_t waveshape[] PROGMEM =
{
0, 1, 2, 3, 4, 5, 6, 7,
8, 9, 10, 11, 12, 13, 14, 15,
16, 17, 18, 19, 20, 21, 22, 23,
24, 25, 26, 27, 28, 29, 20, 31
};
*/
// sinusoidal waveform created in Excell / Libreoffice
const uint8_t waveshape[] PROGMEM =
{ 18, 21, 23, 26, 27, 29, 30, 30,
30, 29, 27, 26, 23, 21, 18, 15,
12, 9, 7, 4, 3, 1, 0, 0,
0, 1, 3, 4, 7, 9, 12, 15
};
int main(void)
{
uint8_t sequence;
uint8_t frequency;
uint8_t dacvalue;
uint8_t delayusec;
// SET OUTPUT PIN ON ALL OUTPUT PORTS
OUTPUTPORTCTRL = 0b00011111; //set all 5 LOWER bit pins as output
OUTPUTPORT = 0b00000000; //set all 5 LOWER bit pins to ZERO
//* neverending loop */
while (1)
{
// generating WAVE on BIT0-BIT5 DAC outputs
// with values taken from PROGMEM WAVE definition
/*
// gives exact 26,5 kHz with 16MHz clock of ATTINY85
for(sequence=0; sequence<31; sequence++)
{
dacvalue = pgm_read_byte(waveshape + sequence) ;
OUTPUTPORT = dacvalue;
// now delay to achieve desired frequency
asm volatile (
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n" );
};
// gives exact 25,8 kHz with 16MHz clock of ATTINY85
for(sequence=0; sequence<31; sequence++)
{
dacvalue = pgm_read_byte(waveshape + sequence) ;
OUTPUTPORT = dacvalue;
// now delay to achieve desired frequency
asm volatile (
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n" );
};
*/
// gives exact 24,6 kHz with 16MHz clock of ATTINY85
for(sequence=0; sequence<31; sequence++)
{
dacvalue = pgm_read_byte(waveshape + sequence) ;
OUTPUTPORT = dacvalue;
// now delay to achieve desired frequency
asm volatile (
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n" );
};
/*
// gives exact 23,5 kHz with 16MHz clock of ATTINY85
for(sequence=0; sequence<31; sequence++)
{
dacvalue = pgm_read_byte(waveshape + sequence) ;
OUTPUTPORT = dacvalue;
// now delay to achieve desired frequency
asm volatile (
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n"
" nop \n" );
};
*/
}; // neverending loop
}; // end of MAIN