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
|
#include "pb.h"
#include "pb.h"
#include "pb-types.h"
#include "pb-mod.h"
#include "pb-send.h"
#include <hardware/i2c.h>
#include <hardware/gpio.h>
#include <pico/i2c_slave.h>
#include <pico/stdio.h>
#include <FreeRTOS.h>
#include <stdio.h>
#include <timers.h>
#define PB_I2C_S i2c0
#define PB_I2C_M i2c1
#define BUF_SIZE 256
#define MSGS_MAX 4
typedef struct {
uint8_t data[BUF_SIZE];
size_t size;
} i2c_msg_buf_t;
static i2c_msg_buf_t msgs[MSGS_MAX];
static size_t msg_index = 0;
static void async_pb_i2c_recv(void * _msg, uint32_t _) {
i2c_msg_buf_t * msg = _msg;
pb_i2c_recv(msg->data, msg->size);
}
static void msg_complete(i2c_msg_buf_t * msg) {
return pb_i2c_recv(msg->data, msg->size);
// defer pb_i2c_recv call to FreeRTOS scheduler as pb_i2c_recv takes
// too long to return from an ISR
xTimerPendFunctionCallFromISR(async_pb_i2c_recv, msg, 0, NULL);
// prepare next message for use
msg_index = (msg_index + 1) % MSGS_MAX;
msgs[msg_index].size = 0;
}
// This function is called from the I2C ISR
static void recv_event(i2c_inst_t *i2c, i2c_slave_event_t event) {
i2c_msg_buf_t * msg = &msgs[msg_index];
switch (event) {
case I2C_SLAVE_RECEIVE: {
if (msg->size == BUF_SIZE) return;
msg->data[msg->size++] = i2c_read_byte_raw(PB_I2C_S);
break;
}
case I2C_SLAVE_FINISH: {
msg_complete(msg);
break;
}
default: break;
}
}
void pb_setup() {
i2c_init(PB_I2C_S, PB_CLOCK_SPEED_HZ);
i2c_init(PB_I2C_M, PB_CLOCK_SPEED_HZ);
i2c_slave_init(PB_I2C_S, PB_MOD_ADDR, &recv_event);
}
__weak void pb_i2c_send(i2c_addr_t addr, const uint8_t * buf, size_t sz) {
// false to write stop condition to i2c bus
i2c_write_timeout_us(PB_I2C_M, addr, buf, sz, false, PB_TIMEOUT_US);
}
void pb_mod_blocking_delay_ms(unsigned long ms) {
vTaskDelay(ms / portTICK_PERIOD_MS);
}
|