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
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
|
#include "stm32.h"
#include "interrupt.h"
#include "thread.h"
#include "time.h"
#include "ppmsum.h"
#include "i2c.h"
#include "itg3200.h"
#include "bma150.h"
#include "usart.h"
#include "xbee.h"
template<class T>
inline void saturate(T& var, T absmax) {
if(var > absmax) {
var = absmax;
} else if(var < -absmax) {
var = -absmax;
}
}
template<class T>
inline T limit(T var, T min, T max) {
if(var < min) {
return min;
} else if(var > max) {
return max;
} else {
return var;
}
}
class PID {
private:
uint16_t Kp, Ki, Kd;
int16_t last;
int32_t accum;
public:
PID(uint16_t p, uint16_t i, uint16_t d) : Kp(p), Ki(i), Kd(d), last(0), accum(0) {}
int16_t update(int16_t error) {
// P
int32_t corr_p = Kp * error;
// I
accum += Ki * error;
int32_t corr_i = accum;
// D
int32_t corr_d = Kd * (error - last);
last = error;
return (corr_p + corr_i + corr_d) >> 16;
}
};
I2C i2c;
ITG3200 gyro(i2c);
BMA150 accel(i2c);
void threadmain() {
while(1) {
uint16_t buf[] = {
gyro.x,
gyro.y,
gyro.z,
accel.x,
accel.y,
accel.z,
};
xbee_send(1, sizeof(buf), (uint8_t*)buf);
Time::sleep(100);
}
}
uint32_t thstack[1024];
Thread thread(thstack, sizeof(thstack), threadmain);
int main() {
// Initialize system timer.
Time::init();
RCC.enable(RCC.AFIO);
RCC.enable(RCC.IOPA);
RCC.enable(RCC.IOPB);
GPIOA.CRL = 0x4444bbbb;
GPIOA.CRH = 0x444444b4;
GPIOB.CRL = 0xff444434;
GPIOB.CRH = 0x44444444;
GPIOB.ODR = 1 << 1;
Time::sleep(10);
//I2C i2c;
i2c.enable();
//ITG3200 gyro(i2c);
gyro.init();
accel.init();
PPMSum ppmsum;
ppmsum.enable();
RCC.enable(RCC.TIM2);
TIM2.PSC = 72;
TIM2.ARR = 5000;
TIM2.CCER = 0x1111;
TIM2.CCMR1 = 0x6868;
TIM2.CCMR2 = 0x6868;
TIM2.CR1 = 0x05;
PID pid_pitch(6000, 0, 0);
PID pid_roll(6000, 0, 0);
PID pid_yaw(6000, 0, 0);
usart_enable();
thread.start();
while(1) {
// Wait for a new update.
while(!(TIM2.SR & 0x01)) {
Thread::yield();
}
TIM2.SR = 0;
// Read sensors.
gyro.update();
accel.update();
// Update filter.
// Generate motor mix.
int16_t throttle = ppmsum.channels[2] - 1000;
int16_t pitch = pid_pitch.update((ppmsum.channels[1] - 1500) * 1 - gyro.x);
int16_t roll = pid_roll.update((ppmsum.channels[0] - 1500) * 1 - gyro.y);
int16_t yaw = pid_yaw.update((ppmsum.channels[3] - 1500) * -1 - gyro.z);
int16_t max = throttle > 250 ? 250 : throttle;
saturate(pitch, max);
saturate(roll, max);
saturate(yaw, max);
int cmds[] = {
1000 + throttle + pitch - roll + yaw,
1000 + throttle - pitch - roll - yaw,
1000 + throttle - pitch + roll + yaw,
1000 + throttle + pitch + roll - yaw,
};
TIM2.CCR1 = limit(cmds[0], 1000, 2000);
TIM2.CCR2 = limit(cmds[1], 1000, 2000);
TIM2.CCR3 = limit(cmds[2], 1000, 2000);
TIM2.CCR4 = limit(cmds[3], 1000, 2000);
}
}
|
