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--- en:iot-open:practical:hardware:sut:stm32:iot_1 [2024/04/25 20:18] – [STM_IoT_1: Reading MAC address of the WiFi] ktokarz
+++ en:iot-open:practical:hardware:sut:stm32:iot_1 [2024/04/27 08:15] (current) – [Result validation] ktokarz
@@ Line 6: / Line 6: @@
 ===== Prerequisites =====
 To implement this scenario, it is necessary to get familiar with at least one of the following scenarios first:
+  * [[en:iot-open:practical:hardware:sut:stm32:IoT_AT]],
   * [[en:iot-open:practical:hardware:sut:stm32:emb5_1|]],
   * [[en:iot-open:practical:hardware:sut:stm32:emb6_1|]],
@@ Line 30: / Line 31: @@
 === Step 1 ===
-Include the WiFi management library in your source code:
+Include the LCD library in your source code:
 <code c>
-#include <WiFi.h>
+#include "LiquidCrystal.h"
 </code>
-The WiFi library automatically initialises a singleton class ''WiFi'' that you can use to set up working mode, read MAC, and perform many other operations.
+Create objects of the LCD and Hardware Serial classes:
+<code c>
+// Serial port class and configuration (Constructor uses STM port numbering)
+HardwareSerial WiFiSerial(RxD_PIN, TxD_PIN, NC, NC);
+// LCD class
+const int rs = PC5, en = PB11, d4 = PB12, d5 = PB13, d6 = PB14, d7 = PB15;
+LiquidCrystal lcd(rs, en, d4, d5, d6, d7);
+</code>
+Declare two variables with the strings to be compared with the responses from the WiFi module.
+<code c>
+String compOK;
+String compERROR;
+</code>
 === Step 2 ===
-Reading the MAC as a ''String'' is as easy as simply calling:
+In the Setup() function initialise the serial port, display, and strings.
 <code c>
-  WiFi.macAddress();
+WiFiSerial.begin(115200);
+lcd.begin(16, 2);
+compOK = "OK";
+compERROR = "ERROR";
 </code>
-==== Result validation ====
+We will use the code template from [[en:iot-open:practical:hardware:sut:stm32:IoT_AT]] to communicate with the WiFi module. The first command we will send "AT" to confirm that everything works properly:
-Using another node should change the MAC read. Book another device and discover its MAC.
+<code c>
+WiFiSerial.println("AT");
+lcd.setCursor(0,0);
+lcd.print("AT              ");
+do {
+  response = WiFiSerial.readStringUntil(0x0A);
+  lcd.setCursor(0,1);
+  lcd.print(response);
+} while (!(response.startsWith(compOK)));
-===== FAQ =====
+delay(1000);
-**Can I change MAC?**: Actually, yes, you can. It is not advised, however, because you may accidentally generate an overlapping address that will collide with another device in the same network. You must first explicitly configure the ESP32 chip to work as an AP (Access Point, Server) or STA (WiFi Client) to do it. Sample stub code (for STA) may look as follows:
+</code>
+The next command can be the "AT+CIPSTAMAC?" which returns the MAC address in the response message which looks like this:
 <code c>
-#include <WiFi.h>
++CIPSTAMAC:"84:fc:e6:88:63:d1"
-#include <esp_wifi.h>
+</code>
-uint8_t newMAC[] = {0xDE, 0xAD, 0xBE, 0xEF, 0xCA, 0xFE}; //Array of bytes with new MAC
+We can implement the part of displaying the MAC by repeating the block of the code similar to the one presented above with two modifications. Change the "AT" command, and add inside the code the following lines:
-void setup()
+<code c>
-{
+if (response.startsWith("+CIPSTAMAC")) {
-  WiFi.mode(WIFI_STA);
+  response.remove(0,12);
-  esp_wifi_set_mac(WIFI_IF_STA, &newMAC[0]);
+  lcd.setCursor(0,0);
+  lcd.print(response);
 }
 </code>
+==== Result validation ====
+You should be able to see the MAC address of the ESP32-C3 module.
+<note>
+Using another node should change the MAC read. Book another device and discover its MAC.
+</note>
+<note info>
+Because LCD can't properly display some non-visible characters the presented code sometimes shows additional, non-letter characters. It is out of the scope of this scenario to filter these characters out. We leave the task of making visual improvements to your invention.
+</note>
+===== FAQ =====
+**Can I change MAC?**: Actually, yes, you can. It is not advised, however, because you may accidentally generate an overlapping address that will collide with another device in the same network.
 <WRAP noprint>

en/iot-open/practical/hardware/sut/stm32/iot_1.1714076316.txt.gz · Last modified: 2024/04/25 20:18 by ktokarz