APC220 not receiving data

[timarh]

Hello,

I am using a pair of APC220 modules to communicate data from sensor from one place to another using 2 arduinos. I am currently learning how they work and am trying to send a string from one apc to another. However, this doesn't work. I assume that the APC220 is sending data, because the tx lamp is flashing, however on the receiving arduino i do not see the rx lamp flashing. I have checked the wires and checked if they both have the same settings. Does anyone have an idea of what the problem could be?

Code for the transmitting arduino:

#include <SoftwareSerial.h>
#define rxPin 10
#define txPin 9

SoftwareSerial mySerial(txPin,rxPin);
int number = 0;

void setup() {

Serial.begin(9600);
  mySerial.begin(9600);

}

void loop() {
(number ++);
Serial.print ("APC220 Erik test   ");
Serial.println (number);
mySerial.print ("APC220 Erik test   ");
mySerial.println (number);
delay (1000);
}

Code for the receiving arduino

#include <SoftwareSerial.h>

SoftwareSerial mySerial(2, 3); 

void setup() {
  Serial.begin(9600);
  mySerial.begin(9600);
}

void loop() {
  if(mySerial.available() > 1){
    String input = mySerial.readString();
    Serial.println(input);    
  }
  delay(100);
}

[jremington]

@timarh

SoftwareSerial mySerial(txPin,rxPin);

Looks like you have the pin assignments backward.

SoftwareSerial reference page

[Railroader]

Powering a transmitter from the controller may be a reason for trouble. It's bad design using the controller as a power supply for motors, transmitter etc.
If You're lucky if things just don't work. If You're unlucky the controller board gets damaged.

[gilshultz]

@timarh

Does anyone have an idea of what the problem could be?

Power Stability Issues with RF24 Radio Modules

As described in the RF24 Common Issues Guide, radio modules, especially the PA+LNA versions, are highly reliant on a stable power source. The 3.3V output from Arduino is not stable enough for these modules in many applications. While they may work with an inadequate power supply, you may experience lost packets or reduced reception compared to modules powered by a more stable source.

Symptoms of Power Issues:

• Radio module performance may improve when touched, indicating power stability issues.
• These issues are often caused by the absence of a capacitor, a common cost-saving omission by some manufacturers.

Temporary Patch :

• Add Capacitors: Place capacitors close to the VCC and GND pins of the radio module. A 10uF capacitor is usually sufficient, but the exact value can depend on your circuit layout.
• Use Low ESR Capacitors: Capacitors with low Equivalent Series Resistance (ESR) are recommended, as they provide better power stability and performance.

Adding the appropriate capacitors can greatly improve the reliability of your RF24 module by ensuring a stable power supply, thus minimizing packet loss and enhancing overall performance. A separate power supply for the radios is the best solution.

There is no link to the part being used so I took a SWAG:
nRF24L01 Features
2.4GHz RF transceiver Module
Operating Voltage: 3.3V
Nominal current: 50mA
Range : 50 – 200 feet
Operating current: 250mA (maximum)
Communication Protocol: SPI
Baud Rate: 250 kbps - 2 Mbps.
Channel Range: 125
Maximum Pipelines/node : 6
Low cost wireless solution:

nRF24L01 Wireless RF Module

They also work better if they are at least a meter apart.

[timarh]

I have changed the code for it to match it correctly, but still no luck. serial monitor doesnt show anything

[jremington]

Triple check the wiring, too.

[timarh]

the APC's rx goes into the arduinos tx and the APC's tx goes into the arduinos rx correct? I have checked the wires over and over again, seems like everything is correct.

[jremington]

This is pretty silly for single-character-based communications, especially considering that use of String objects tends to cause AVR-based Arduinos to crash:

  if(mySerial.available() > 1){
    String input = mySerial.readString();
    Serial.println(input);    
  }

A more sensible approach is

while (mySerial.available()) {
Serial.print(mySerial.read());
}

[timarh]

Changed the code, still dont see anything.

[jremington]

https://www.circuits-diy.com/interfacing-apc220-rf-transceiver-module-with-arduino/

[timarh]

The problem is fixed! I have switched to 2 brand new arduino's and new jumper wires. The problem was probably in one of the jumper wires, but im not sure.