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
|
// Sample i2c master example for development i2c branch. Writes 0-63 to
// addresses 0-63 on a 24LC256 EEPROM, then reads them back.
#include "wirish.h"
#include "i2c.h"
static const uint8 slave_address = 0b1010001;
#define NR_ELEMENTS 4
uint8 buf0[NR_ELEMENTS + 2] = {0x0, 0x0};
uint8 buf1[] = {0x0, 0x0};
uint8 buf2[NR_ELEMENTS];
i2c_msg msgs[3];
void toggle(void) {
digitalWrite(2, HIGH);
digitalWrite(2, LOW);
}
void setup() {
uint32 i;
pinMode(BOARD_LED_PIN, OUTPUT);
pinMode(2, OUTPUT);
Serial2.begin(9600);
Serial2.println("Hello!");
digitalWrite(2, LOW);
for (i = 2; i < sizeof buf0; i++) {
buf0[i] = i - 2;
}
i2c_master_enable(I2C1, 0);
/* Write some bytes */
msgs[0].addr = slave_address;
msgs[0].flags = 0;
msgs[0].length = sizeof buf0;
msgs[0].data = buf0;
i2c_master_xfer(I2C1, msgs, 1);
delay(5);
}
void loop() {
delay(100);
toggleLED();
/* Write slave address to read */
msgs[1].addr = slave_address;
msgs[1].flags = 0;
msgs[1].length = 2;
msgs[1].data = buf1;
/* Repeated start condition, then read NR_ELEMENTS bytes back */
msgs[2].addr = slave_address;
msgs[2].flags = I2C_MSG_READ;
msgs[2].length = sizeof buf2;
msgs[2].data = buf2;
i2c_master_xfer(I2C1, msgs + 1, 2);
}
// Force init to be called *first*, i.e. before static object allocation.
// Otherwise, statically allocated object that need libmaple may fail.
__attribute__(( constructor )) void premain() {
init();
}
int main(void) {
setup();
while (1) {
loop();
}
return 0;
}
|
