Hello, I have tried to use nrf24l01 with Arduino Uno, but I am encountering some issues. I have already read through Simple nRF24L01+ 2.4GHz transceiver demo - #2 by Robin2 and am using the simpleTx and simpleRx code. I have also tried the CheckConnection before running the main code.
The issues I am encountering are:
Sometimes the receiver can receive message 0, but when I try it again, it fails to receive any data.
And when it works, it only works on MAX mode(HIGH or LOW isn't stablize), is it because I am using nrf24l01+pa-lna?
The return from radio.write() is always 0, regardless of whether the receiver has received the data or not.
like :
And I have tried using a 10µF capacitor, but it doesn't seem to be helpful. When I check the connection, it doesn't work (prints out 0x00... and can't set the power or datarate ).
Hardware
Arduino UNO for both transmitter and receiver
nRF24L01+PA+LNA
PINS
CE 9
CSN 8
MOSI 11
MISO 12
SCK 13
Tx and Rx are the same.
Have you tried moving the radios apart by a few meters? The high power modules can have trouble talking if too close together. And/or lower the power.
Please post a wiring diagram. Written descriptions are always more ambiguous than a drawing. Hand drawn, photographed and posted is fine. Include all pin names/numbers, components, their part numbers and/or values and power supplies.
Please post clear photos of your wiring.
Does that mean the CheckConnection.ino program from Robin2's tutorial? Did you run the program for both radio modules?
You have CE and CSN wire to pins 8 and 9. Did you change those pins in the CheckConnection code? CE and CSN are set to pins 9 and 10 in the program.
#define CE_PIN 9
#define CSN_PIN 10
Make sure the rf24 power supply can provide enough current. This is especially true for the high power (external antenna) modules. I use homemade adapters like these. They are powered by 5V and have a 3.3V regulator on the board. Robin2 also has suggested trying with a 2 AA cell battery pack.
OK, I will try using a 2AA cell battery. (I have tested the voltage from the Uno's 3.3V pin, and it seems to be supplying around 3.6 volts. Isn't it enough?)
Thanks!
It is not so much the voltage that may be lacking, it is the capacity for the supply to handle the current demand. The radios consume current in brief bursts when transmitting. If you are watching the voltage with a DMM it is probably too slow to catch the dips in the supply voltage. A scope could catch them.
The Uno 3.3V supply may not handle the surge of current that the radio needs, so the 10 to 100uF cap is suggested to help to supply that surge. The cap needs to be as close to the module as possible. With the high power radios, even the cap may not be enough so one must resort to an external supply, like the batteries. I prefer the adapter that I linked in the previous post. It runs off the Uno 5V and I have never had power related problems.
