diff options
| -rw-r--r-- | main/i2c.c | 62 | ||||
| -rw-r--r-- | main/i2c.h | 8 | ||||
| -rw-r--r-- | main/main.c | 2 |
3 files changed, 70 insertions, 2 deletions
@@ -8,7 +8,7 @@ void init_i2c() { stdio_init_all(); - i2c_init(i2c_default, 100 * 1000); + i2c_init(i2c_default, 100 * 1000); // currently at 100kHz // Initialize I2C pins - sda(16), scl(17) gpio_set_function(SDA_PIN, GPIO_FUNC_I2C); @@ -27,3 +27,63 @@ 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(); + } + } + +} @@ -6,6 +6,7 @@ #define SDA_PIN 16 #define SCL_PIN 17 +#define MAX_SLAVES 10 /** * \brief initialize all required gpio for i2c usage on the pico @@ -28,9 +29,14 @@ int read_i2c(uint8_t addr, uint8_t *output, size_t len); /** * \brief write data to addr with length len from i2c bus. - * + * \param addr + * \param input + * \param len * This functions writes data to a specific address on the i2c bus, * the input var holds the data which will be written to the given * address with length len. */ int write_i2c(uint8_t addr, uint8_t *input, size_t len); + +/** \brief looking for slave addresses and requesting updates */ +void bus_task(); diff --git a/main/main.c b/main/main.c index 73b6708..b38030f 100644 --- a/main/main.c +++ b/main/main.c @@ -7,6 +7,7 @@ #include "config.h" #include "init.h" #include "sock.h" +#include "i2c.h" void blink_task() { await_init(); // `blink_task` uses GPIO @@ -24,6 +25,7 @@ int main() { xTaskCreate((TaskFunction_t) blink_task, "blink", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY + 2, NULL); xTaskCreate((TaskFunction_t) serve_task, "serve", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY + 2, NULL); + xTaskCreate((TaskFunction_t) bus_task, "bus", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY + 2, NULL); vTaskStartScheduler(); } |