First commit

Makefile

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+#
+# This is a project Makefile. It is assumed the directory this Makefile resides in is a
+# project subdirectory.
+#
+
+PROJECT_NAME := i2c-scanner
+
+include $(IDF_PATH)/make/project.mk
+

README.md

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+# I2C Scanner 
+
+Starts a FreeRTOS task to scan I2C Bud
+
+ESP32  -- SDA (21) -- SCL (22)
+
+

main/component.mk

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+#
+# "main" pseudo-component makefile.
+#
+# (Uses default behaviour of compiling all source files in directory, adding 'include' to include path.)
+

main/main.c

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+#include <driver/i2c.h>
+#include <esp_log.h>
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+#include <stdio.h>
+#include "sdkconfig.h"
+
+#define SDA_PIN 21 
+#define SCL_PIN 22
+
+static char tag[] = "i2cscanner";
+
+void task_i2cscanner(void *ignore) {
+	ESP_LOGD(tag, ">> i2cScanner");
+	i2c_config_t conf;
+	conf.mode = I2C_MODE_MASTER;
+	conf.sda_io_num = SDA_PIN;
+	conf.scl_io_num = SCL_PIN;
+	conf.sda_pullup_en = GPIO_PULLUP_ENABLE;
+	conf.scl_pullup_en = GPIO_PULLUP_ENABLE;
+	conf.master.clk_speed = 100000;
+	i2c_param_config(I2C_NUM_0, &conf);
+
+	i2c_driver_install(I2C_NUM_0, I2C_MODE_MASTER, 0, 0, 0);
+
+	int i;
+	esp_err_t espRc;
+	printf("     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f\n");
+	printf("00:         ");
+	for (i=3; i< 0x78; i++) {
+		i2c_cmd_handle_t cmd = i2c_cmd_link_create();
+		i2c_master_start(cmd);
+		i2c_master_write_byte(cmd, (i << 1) | I2C_MASTER_WRITE, 1 /* expect ack */);
+		i2c_master_stop(cmd);
+
+		espRc = i2c_master_cmd_begin(I2C_NUM_0, cmd, 10/portTICK_PERIOD_MS);
+		if (i%16 == 0) {
+			printf("\n%.2x:", i);
+		}
+		if (espRc == 0) {
+			printf(" %.2x", i);
+		} else {
+			printf(" --");
+		}
+		//ESP_LOGD(tag, "i=%d, rc=%d (0x%x)", i, espRc, espRc);
+		i2c_cmd_link_delete(cmd);
+	}
+	printf("\n");
+	vTaskDelete(NULL);
+}
+
+void app_main(void)
+{
+	xTaskCreate(&task_i2cscanner, "i2c scanner",  2048, NULL, 6, NULL);
+}
+