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#include "i2c.h"
#include <stdio.h>
#include <stddef.h>
#include <stdint.h>
#include <pico/stdlib.h>
#include <hardware/i2c.h>
void init_i2c() {
stdio_init_all();
i2c_init(i2c_default, 100 * 1000); // currently at 100kHz
// Initialize I2C pins - sda(16), scl(17)
gpio_set_function(SDA_PIN, GPIO_FUNC_I2C);
gpio_set_function(SCL_PIN, GPIO_FUNC_I2C);
gpio_pull_up(SDA_PIN);
gpio_pull_up(SCL_PIN);
}
int read_i2c(uint8_t addr, uint8_t *output, size_t len) {
// false - finished with bus
return i2c_read_blocking (i2c_default, addr, output, len, false);
}
int write_i2c(uint8_t addr, uint8_t *input, size_t len) {
// true to keep master control of bus
return i2c_write_blocking (i2c_default, addr, input, len, true);
}
bool reserved_addr(uint8_t addr) {
return (addr & 0x78) == 0 || (addr & 0x78) == 0x78;
}
void init_addr_array(uint8_t array[]) {
for(int i = 0; i < MAX_SLAVES; i++){
array[i] = 0x00;
}
}
uint8_t scan_bus(uint8_t array[]) {
int ret;
int i = 0;
uint8_t rxdata;
for(int addr = 0; addr < (1<<7); addr++) {
// ignore reserved addresses
// These are any addresses of the form 000 0xxx or 111 1xxx
if( reserved_addr(addr) ){
ret = PICO_ERROR_GENERIC;
}else{
ret = i2c_read_blocking(i2c_default, addr, &rxdata, 1, false);
}
// if acknowledged -> ret == number of bytes sent
if(ret > 0){
array[i] = addr;
i++;
}
}
return array;
}
void bus_task() {
// scan bus for slaves
// send updates at regular intervals
int i = 0;
uint8_t *found[MAX_SLAVES];
init_addr_array(&found);
while(1) {
scan_bus(&found);
for(int i = 0; i < MAX_SLAVES; i++){
if( found[i] == 0x00 )
break;
// send data to found slave address
write_i2c(found[i], 0x01, 1);
write_i2c(found[i], 0x00, 1);
// request update from slave addr at found[i]
//write_i2c();
}
}
}
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