NRF24L01 2.4GHz RF Module

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Overview

A low-power wireless communication module using 2.4GHz frequency. Primarily used for transmitting and receiving data in applications such as IoT and wireless sensor networks. Uses SPI interface.

Specifications

IC：nRF24L01P
Frequency：2.4~2.525GHz
Power：20dBm
Distance：2.5km
Interface：SPI

Supported GPIO

Raspberry Pi 0~4
Raspberry Pi 5
BeagleBone Black/Green
Jetson Nano
FT232H, FT2232H, FT4232H

Commands

[INIT]

Enters initial configuration settings.

Item	Type	Description
ID	WRITE	Enter the module ID (address) in the range 0~255. The ID must be unique for each module and cannot be duplicated.
CE Pin	WRITE	Enter the GPIO number connected to the module’s CE pin.
Communication Speed	WRITE	Select the communication speed. Must match the communication speed of the counterpart.
Channel (0~125)	WRITE	Enter the communication channel in the range 0~125. Corresponds to the ISM band range of 2.400 ~ 2.525GHz, with each channel having a bandwidth of 1MHz. Must match the communication channel of the counterpart.

[SEND]

Transmits data. Can send up to 32 bytes of data.

Item	Type	Description
Recipient ID	WRITE	Enter the ID (address) of the recipient to send data to in the range 0~255.
Data	WRITE	Enter the data to send. Text format, up to 32 bytes can be sent.
Acknowledgment Request	WRITE	Select whether to request an acknowledgment signal (ACK) from the recipient confirming that they received the data after sending. If an acknowledgment request is sent but the recipient does not send an acknowledgment response, the data will be retransmitted up to 16 times. Recommended for environments where communication reliability is more important.

[RECV]

Receives data.

Item	Type	Description
Data	READ	Select a text type variable to store the received data.

Example

Objective

Use two NRF24L01 modules to exchange data.

Parts

Part	Quantity
Raspberry Pi 4 *	2
NRF24L01	2
10μF Electrolytic Capacitor (Optional) **	2
0.1μF Ceramic Capacitor (Optional) ***	2

* Other hardware can also be used. Refer to Supported GPIO.
** The NRF24L01 module requires momentarily high current when transmitting data. If the power supply cannot respond fast enough, voltage drops may occur. Connecting a 10μF capacitor between 3.3V and GND can prevent this problem. Not necessary for testing purposes.
*** The NRF24L01 module uses high-frequency signals, which can cause noise on the power lines. The 0.1μF capacitor filters high-frequency noise, improving module stability. Connect in parallel with the 10μF capacitor. Not necessary for testing purposes.

Wiring

Connect the following pins horizontally to each other. (2 sets)

NRF24L01 *	10μF Electrolytic Capacitor	0.1μF Ceramic Capacitor	GPIO
	+ Pin		3.3V
	– Pin		GND
		Pin 1	3.3V
		Pin 2	GND
VCC			3.3V
GND			GND
SCLK			11 (SPI0 SCLK)
MISO			9 (SPI0 MISO)
MOSI			10 (SPI0 MOSI)
CSN			8 (SPI0 CE0)
CE			23 **