Obtaining Mac Address from ESP32-S3-Zero

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1

I recently purchased a couple of ESP-S3-Zero to replace a pair of ESP32-C3-Zero that operate in a peer - peer mode. I was able to get the Mac Addresses from the ESP32-C3-Zero with any issues but when tried the ESP32-S3-Zero it was a no go, all I got was “16:26:20.526 → ESP-ROM:esp32s3-20210327” which appears to be the firmware version. I’ve done exhaustive internet search, can anyone give me some help. Thanks

2

There are more then one mac address, so some tweaking may be needed.
The base mac address is the one used by wifi (unless changed), then others are based on that.

src: Miscellaneous System APIs - ESP32 - — ESP-IDF Programming Guide v5.2.5 documentation
example

#include "esp_mac.h"

 uint8_t MAC[6];
    esp_read_mac(MAC, ESP_MAC_BASE);
    printf ("MAC Addr:  %02X:%02X:%02X:%02X:%02X:%02X\n",MAC[0],MAC[1],MAC[2],MAC[3],MAC[4],MAC[5]);

From above on my S3 I get
MAC Addr: 3C:84:27:CA:65:B4
which is the one on the wifi station connected to my AP
3c-84-27-ca-65-b4
Some notes

ESP_MAC_WIFI_STA		MAC for WiFi Station (6 bytes)
ESP_MAC_WIFI_SOFTAP		MAC for WiFi Soft-AP (6 bytes)
ESP_MAC_BT			MAC for Bluetooth (6 bytes)
ESP_MAC_ETH			MAC for Ethernet (6 bytes)
ESP_MAC_IEEE802154		if CONFIG_SOC_IEEE802154_SUPPORTED=y, 
				MAC for IEEE802154 (8 bytes)

ESP_MAC_BASE			Base MAC for that used for other MAC types (6 bytes)
ESP_MAC_EFUSE_FACTORY		MAC_FACTORY eFuse which was burned by Espressif in production (6 bytes)
ESP_MAC_EFUSE_CUSTOM		MAC_CUSTOM eFuse which was can be burned by customer (6 bytes)
ESP_MAC_EFUSE_EXT		if CONFIG_SOC_IEEE802154_SUPPORTED=y, 
				MAC_EXT eFuse which is used as an extender 
				for IEEE802154 MAC (2 bytes)


Wi-Fi Station	base_mac			
Wi-Fi SoftAP	base_mac, +1 to the last octet	
Bluetooth	base_mac, +2 to the last octet
Ethernet	base_mac, +3 to the last octet
3

Hi Michael,

Thanks for your reply,

I copied and pasted into IDE selected the correct board 'Waveshare
ESP32-S3-Zero but I run the compiler I get the following error,

C:\Users\alano\AppData\Local\Temp.arduinoIDE-unsaved2025223-2352-1vhj7fw.h0etl\sketch_mar23a\sketch_mar23a.ino:4:17:
error: expected constructor, destructor, or type conversion before ‘(’ token
4 | esp_read_mac(MAC, ESP_MAC_BASE);
> ^
C:\Users\alano\AppData\Local\Temp.arduinoIDE-unsaved2025223-2352-1vhj7fw.h0etl\sketch_mar23a\sketch_mar23a.ino:5:12:
error: expected constructor, destructor, or type conversion before ‘(’ token
5 | printf (“MAC Addr:
%02X:%02X:%02X:%02X:%02X:%02X\n”,MAC[0],MAC[1],MAC[2],MAC[3],MAC[4],MAC[5]);
> ^

exit status 1

Compilation error: expected constructor, destructor, or type conversion
before ‘(’ token

All the best

Alan

4

What is the code you are using? This works for the Arduino IDE:


#include "esp_mac.h"

void setup() {
  Serial.begin(115200);

  // Variable to store the MAC address
  uint8_t MAC[6];

  // Get Base MAC address
  esp_read_mac(MAC, ESP_MAC_BASE);
  printf ("MAC Addr:  %02X:%02X:%02X:%02X:%02X:%02X\n",MAC[0],MAC[1],MAC[2],MAC[3],MAC[4],MAC[5]);
}

void loop() {}
5

Hi Jeff,

Thanks for reply,

I’m using Aduino IDE 2.3.4

You code compiles and I’ve run it using the “Waveshare ESP32-S3-Zero” and the generic “ESP32S3 Dev Module” but all that is displayed is the ROM detail.

Thanks Again

Alan

6

I can only test with a C3 rather than an S3, but I believe for the ‘mini’ they work the same. You need to set up a separate IDE session and connect it with a second USB to serial converter to the S3 UART TX pin, set the second instance of the IDE to that second virtual COM port, and read the console output using the console feature of that IDE.

Another option is to configure the MCU with a simple I2C text display module and display the MAC details to that device.

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7

Thanks Jeff ,

I’ll consider the option and yes getting the Mac Address out of a C3 is snack but these C6s are another beast.

Thanks again keep well

Alan

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8

Note that if it’s the STA or SOFTAP MAC that you are after you can load up the appropriate sample application and it will show up on your router as new wireless connection (for STA) or on your phone as a new hotspot (for SOFTAP).

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