HM10 not returning AT signals

I am using an HM10 Bluetooth module and am trying to follow this tutorial to use AT commands. Unfortunately, none of my AT commands get any response when I use the serial monitor. I followed the tutorial's exact wiring and copy-pasted the code. I have all the same serial monitor settings (Both NL & CR, 9600 Baud, etc...), but still don't get a response when I send AT through the serial monitor. I don't know if this is relevant, but I am using a genuine Arduino Micro and have Arduino 1.8.15 installed on macOS Big Sur.

Omg I just had the same problem with my board a week ago and here is how I fixed it.

//  Sketch: HM-10_Example_04A_RemoteLightSensor
//  Master HM-10
//  Pins
//  BT VCC to Arduino 5V out. 
//  BT GND to GND
//  Arduino D8 (ASS RX) - BT TX no need voltage divider 
//  Arduino D9 (ASS TX) - BT RX through a voltage divider
//  Remote HM-10
//  HM-10 vcc to +5V
//  HM-10 GND to GND
//  HM-10 PIOB to LDR/CDS
#include <AltSoftSerial.h>
AltSoftSerial BTSerial; 
char c=' ';
char reply[30];
int pos = 0;
void setup() 
    Serial.print("Sketch:   ");   Serial.println(__FILE__);
    Serial.print("Uploaded: ");   Serial.println(__DATE__);
    Serial.println(" ");
    Serial.println("The HM-10s should be set for auto connect");
    Serial.println("The remote HM-10 should be set for MODE1");
    Serial.println("BTserial started at 9600");
    Serial.println(" ");
void loop()
    pos = 0;
    while ( BTSerial.available() )
        c =;
        reply[pos] = c;
    reply[pos] = '\0';
    Serial.print("Reply = "); Serial.println(reply); 
    delay (3000);

Upload the code above (install the altSoftSerial library), and when in the serial monitor, click the last option (nr and cl). Send AT and you should get OK.
Here is a link that will save you tons of time and stress, it’s what helped me the most.

Nope, still not working. This is what I see in my serial monitor:
23:03:12.766 -> Reply =
23:03:16.257 -> Reply =
23:03:19.744 -> Reply =
23:03:23.260 -> Reply =
23:03:26.761 -> Reply =
23:03:30.260 -> Reply =
23:03:33.768 -> Reply =
23:03:37.263 -> Reply =
23:03:40.739 -> Reply =
23:03:44.256 -> Reply =
23:03:47.747 -> Reply =
23:03:51.266 -> Reply =
23:03:54.764 -> Reply =

@a43nigam, your topic has been moved to a more suitable location on the forum. At the moment that you can upload a sketch, it's not a topic for Installation and Troubleshooting :wink: See About the Installation & Troubleshooting category.

Have you figured it out yet?

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