# KS0174 keyestudio HM-10 Bluetooth-4.0 V2

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## 1. Introduction

keyestudio HM-10 Bluetooth-4.0 V2 adopts TI CC2541 chip, configuration space of 256Kb.
It supports AT command. Users can modify working mode (master/slave), baud rate, device name, paring password, etc.

## 2. Specification

- Bluetooth protocol: Bluetooth Specification V4.0 BLE
- No byte limit in serial port Transceiving
- In open environment, realize 100m ultra-distance communication with iphone4s
- USB protocol: USB V2.0
- Working frequency: 2.4GHz ISM band
- Modulation method: GFSK(Gaussian Frequency Shift Keying)
- Transmission power: -23dbm, -6dbm, 0dbm, 6dbm, can be modified by AT command.
- Sensitivity: ≤-84dBm at 0.1% BER
- Transmission rate: Asynchronous: 6K bytes ; Synchronous: 6k Bytes
- Security feature: Authentication and encryption
- Supporting service: Central & Peripheral UUID FFE0, FFE1
- Power consumption: Auto sleep mode, stand by current 400uA~800uA, 8.5mA during transmission.
- Power supply: 5V DC
- Working temperature: –5 to +65 Centigrade

## 3. Circuit Connection

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## 4. Sample Code

Download  Resource  : [Resource](./Resource.7z)

```c
int val; 
int ledpin=13; 

void setup() 
{ 
  Serial.begin(9600);
  pinMode(ledpin,OUTPUT); 
} 

void loop()
{ 
    val=Serial.read(); 
    if(val=='a')
    { 
        digitalWrite(ledpin,HIGH); 
        delay(250); 
        digitalWrite(ledpin,LOW); 
        delay(250);
        Serial.println("keyestudio");
    }
}
```

## 5. Result

Open APP HC-COM, click search device, select the device, device is connected; the LED on the Bluetooth module is on. 

Enter “a” in HC-COM, click send, Bluetooth APP will display keyestudio. Every time HC-COM sends an “a”, the Pin13 LED on the main board blinks once.

Note: The above used APP is only compatible with Android system. You need to search BLE Scanner 4.0 to download app in APP store if your use iphone.

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