Added some comments

README.md

@@ -31,6 +31,7 @@ Search 1-Wire devices on bus:
 
 void app_main(void)
 {
+    esp_log_level_set("zh_onewire", ESP_LOG_NONE);
     uint8_t *rom = NULL;
     zh_onewire_init(GPIO_NUM_5);
     if (zh_onewire_reset() != ESP_OK)

zh_onewire.c

@@ -15,10 +15,10 @@
 #define TIME_SLOT_DURATION 120          // Time slot.
 #define VALID_DATA_DURATION 15          // Valid data duration.
 
-#define SKIP_ROM 0xCC
-#define MATCH_ROM 0x55
-#define READ_ROM 0x33
-#define SEARCH_ROM 0xF0
+#define SKIP_ROM 0xCC   // Skip ROM command to address all 1-Wire devices.
+#define MATCH_ROM 0x55  // Match ROM command to address a specific 1-Wire device.
+#define READ_ROM 0x33   // Read ROM command for read ROM on only one 1-Wire device.
+#define SEARCH_ROM 0xF0 // Read ROM on all 1-Wire devices.
 
 #define pgm_read_byte(addr) (*(const uint8_t *)(addr))
 /// \endcond