RF24 VS arduino-ad-mux-lib

Yeah. If you have the main RF24 library installed it's under the examples in "scanner"

No unfortunately I don't. One of the cool things I did learn about the NRF24L01's though is that on the main page run by the guy that is like THE author of the library that everybody uses with them; He has a sketch that you can run and it will scan all of the frequency channels it supports and give you an ascii graph showing which ones it saw signals the most on.

Here is THE library on which 90% of everyone else's libraries are based off of. This guy quite literally wrote the book on these devices. Bookmark this link and treat this guy as the source of truth for all things related to the RF24 series. I recently discovered 8 NRF24L01's that I had stuck away and I've been playing with them for about the past two months and this is my go-to website for anything I want to know about connecting them and using them. 🙃

That's right. Just like Wifi and other radio comms have the ability to vary which specific frequency they make use of, the RF24 line and others give you the ability to choose the default channel. I think each of the available channels is about 100Hz away from each other. Here is the main web page by the author of pretty much the go-to library for the RF24 series of devices. One of the projects he has listed there (if I remember correctly) will go through all of the available channels and give you a psuedo-graphic representation of how much interference it is seeing on each channel in order to hep pick which channel to use so you aren't fighting it out with all of the devices your neighbors might be using with the various devices they have.

I started playing around with my pico and an nrf24L01+ module this week and I was thinking to just hack this a bit more, starting from porting the https://github.com/nRF24/RF24/blob/master/examples_pico/scanner.cpp scanner to micropython.

I used the RF24 library and official datasheet as a reference.

Which Library did you use to interface with the NRF modules? I've tried the RadioHead library and this one but haven't been able to get a successful send/receive between my two Arduinos.

But I didn't know if it worked. I saw a lot of different random signals, but I had no way to know if it was just amplified noise, nor I had a way to know if the downconverter frequency was exactly 2.4GHz, or something else. I have a few cheap nRF24L01 modules around, and plenty of 3.3V Arduino boards, so after a quick read on the nRF24 library (https://github.com/nRF24/RF24), I had a super simple generator running using the carrier wave function of the nRF24.

#include //library for transceiver (nrf24l01+ PA+LNA) https://github.com/nRF24/RF24 #include #include #include //library for multiplexer (74HC4067DB) https://github.com/stechio/arduino-ad-mux-lib using namespace admux; #include //library for display (SSD1306 128x64) https://github.com/adafruit/Adafruit_SSD1306 #include //library for I2C const int sig = A3; //signal pin const int s0 = 2; //address pin 0 const int s1 = 3; //address pin 1 const int s2 = 4; //address pin 2 const int s3 = 5; //address pin 3 const int up1pin = 1; //foward left motor const int down1pin = 0; //backwards left motor const int up2pin = 3; //foward right motor const int down2pin = 2; //backwards right motor const int modifierpin = 4; //pwm speed modifier const int trimmerpin = 5; //pwm trimmer const int navlightpin = 6; //navigation lights const int intlightpin = 7; //interior lights const int extlightpin = 8; //exterior lights const int camerapin = 9; //fpv camera const int autoModepin = 10; //autonomous mode const int CE = 9; //radio CE pin const int CSN = 10; //radio CSN pin const byte address[5] = "00001"; //pipe address float latFromSerial; //parsed lattitude from serial input float lonFromSerial; //parsed longitude from serial input float batteryVoltage; //calculated battery voltage float batteryPercentage; //estimated battery charge int timer; //millis timer const int waypointSize = 50; //number of waypoints const PROGMEM float waypoint[waypointSize][2] = { //waypoints for autoMode() {51.966571, 6.2743379}, {51.966772, 6.2744777}, {51.96699149689901, 6.274366197893084}, {51.9671527562416, 6.274120865412113}, {51.96729645199409, 6.273423270736089}, {51.96743080331666, 6.272665240634041}, {51.96754042621848, 6.271857581899409}, {51.96776236209548, 6.270915330645548}, {51.96798193464908, 6.270221004668555}, {51.96828516667115, 6.269413032485236}, {51.96872940066316, 6.268397202672209}, {51.9690764880844, 6.267825125563484}, {51.96951599079974, 6.267264642338533}, {51.97011340024988, 6.266554277598022}, {51.97066084143675, 6.265542763068586}, {51.97101162702417, 6.264465224751552}, {51.97133799766154, 6.263262306712254}, {51.97164036068298, 6.262353231049387}, {51.97207885573615, 6.261205467922246}, {51.97247264722145, 6.260387048788263}, {51.9730446081463, 6.259285804638093}, {51.97348333946684, 6.258252773125921}, {51.97383500264349, 6.257083089055559}, {51.97411491189212, 6.255751674816601}, {51.97421125024911, 6.254641997085617}, {51.97428144275973, 6.253337927743205}, {51.97438642575778, 6.252258957953291}, {51.97461230120062, 6.251185555711}, {51.97496391672023, 6.250073663806153}, {51.97535356652884, 6.249136612734796}, {51.97593199219659, 6.247849009012851}, {51.97673996614692, 6.246219928264511}, {51.97759975319016, 6.244774079377116}, {51.97970812227523, 6.24269840869726}, {51.98056951741261, 6.241148196857345}, {51.98138148466968, 6.238582344717527}, {51.98226488661611, 6.236909516229776}, {51.9828880442564, 6.236150123494202}, {51.98356664827293, 6.235581737840659}, {51.9846292540927, 6.235086763643169}, {51.98620084359441, 6.234541602496764}, {51.9869680375904, 6.233970146843246}, {51.9884155464398, 6.232522126238424}, {51.98950934373955, 6.231079775783453}, {51.99067711020479, 6.229346290429132}, {51.99142243067518, 6.228071305330573}, {51.99218280844037, 6.226417272538562}, {51.99276345055314, 6.224660968088269}, {51.9928317367713, 6.22340383146351}, {51.99303408040588, 6.222658471539628}, }; int waypointCounter = 0; struct values{ //structure for control values bool up1; bool down1; bool up2; bool down2; int trimmer; int modifier; bool navlight; bool intlight; bool extlight; bool camera; bool autoMode; float targetLat; float targetLon; }; struct info{ //structure for answer from boat int autoMode; int battery; int boatHeading; float boatSpeed; int targetDistance; int targetHeading; }; struct values control; //control values struct info answer; //answer from boat Mux mux(Pinset(s0, s1, s2, s3)); //multiplexer object Adafruit_SSD1306 display(128, 64, &Wire, -1); //display object RF24 radio(CE, CSN); //wireless object void setup() { radio.begin(); //start radio service as transmitter radio.setPALevel(RF24_PA_MIN); //transmission power radio.setDataRate(RF24_250KBPS); //data rate radio.enableAckPayload(); //enable ack payloads radio.setRetries(5,5); //delay, count radio.openWritingPipe(address); //set pipe address radio.stopListening(); //stop listening Serial.setTimeout(10); //set timeout for waiting for incoming data Serial.begin(115200); //set serial baudrate if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { Serial.println(F("SSD1306 allocation failed")); for(;;); // Don't proceed, loop forever } delay(2000); //allow startup of display display.clearDisplay(); //clear the display display.setTextSize(1); //standard 1:1 pixel scale display.setTextColor(WHITE); //set white text display.cp437(true); //use full 256 char 'Code Page 437' font control.targetLat = 51.966451; //default target lattitude control.targetLon = 6.274279; //default target longitude } void loop() { if(millis() - timer >= 100){ //activate every 100 milliseconds timer = millis(); //new timestamp mux.signalPin(sig, INPUT_PULLUP, PinType::Digital); //read all digital switches control.up1 = !mux.read(up1pin); control.down1 = !mux.read(down1pin); control.up2 = !mux.read(up2pin); control.down2 = !mux.read(down2pin); control.navlight = !mux.read(navlightpin); control.intlight = !mux.read(intlightpin); control.extlight = !mux.read(extlightpin); control.camera = !mux.read(camerapin); control.autoMode = !mux.read(autoModepin); mux.signalPin(sig, INPUT, PinType::Analog); //read the analog potentiometers control.modifier = mux.read(modifierpin); control.trimmer = mux.read(trimmerpin); /* if(Serial.available()){ //get target location from serial input latFromSerial = Serial.parseFloat(); //read lattitude lonFromSerial = Serial.parseFloat(); //read longitude if(latFromSerial != 0) //only non zero values control.targetLat = latFromSerial; if(lonFromSerial != 0) //only non zero values control.targetLon = lonFromSerial; } */ control.targetLat = waypoint[waypointCounter][0]; //set target waypoint lattitude control.targetLon = waypoint[waypointCounter][1]; //set target waypoint longitude if(answer.autoMode == 1 && waypointCounter < waypointSize-1) //set next waypoint waypointCounter++; if(control.autoMode && control.camera) //if autoMode is activated use trim potmeter and camera button to override waypoint selection waypointCounter = map(control.trimmer, 0, 1023, 0, waypointSize-1); if(radio.write(&control, sizeof(control))){ //send control values Serial.println(F("Data sent successfully")); if(radio.isAckPayloadAvailable()){ //do we get an answer back? radio.read(&answer, sizeof(answer)); //read answer batteryVoltage = (batteryVoltage+(answer.battery*15.0/1023.0))/2.0; //calculate battery voltage (measured as 1/3th with voltage divider) batteryPercentage = (batteryVoltage-11.5)/(13.0-11.5)*100; //estimate battery charge remaining answerToDisplay(); //put all info on oled display } else{ Serial.println(F("Message received but no answer...")); display.clearDisplay(); //display message for no answer from boat display.setCursor(0, 1); display.print("RC Boat: no answer"); display.display(); } Serial.print((control.targetLat)); Serial.print((" ")); Serial.println((control.targetLon)); } else{ Serial.println(F("Data sending failed")); //display message for no connection to boat display.clearDisplay(); display.setCursor(0, 1); display.print("RC Boat: no contact"); display.display(); } } } void answerToDisplay(){ //function for putting answer from boat on display display.clearDisplay(); display.setCursor(0, 1); display.print("RC Boat: connected!"); display.setCursor(0, 15); display.print("Battery: "); display.print(batteryPercentage, 0); display.print("% "); display.print(batteryVoltage, 1); display.print("V"); display.setCursor(0, 29); display.print("Course: "); display.print(answer.boatHeading); display.print((char)248); display.print(" "); display.print(answer.boatSpeed, 1); display.print("km/h"); display.setCursor(0, 43); display.print("AutoMode: "); if(control.autoMode == 1) display.print(answer.autoMode); else display.print("off"); display.print(" "); display.print(waypointCounter); display.setCursor(0, 57); display.print("Target: "); display.print(answer.targetDistance); display.print("m "); if(answer.targetHeading >= 0) display.print("+"); display.print(answer.targetHeading); display.print((char)248); display.display(); }