Questions tagged [serial]

Serial communication is the standard USB connection between the Arduino and a computer with a standard USB A to B cable or through the TX/RX pins using a USB to serial converter. It can also refer to the serial library.

Filter by
Sorted by
Tagged with
0 votes
1 answer
515 views

CRC8 code not working properly

I need to send a string followed by its CRC8, 0x31 polynomial (= X^8 + X^5 + X^4 + 1), I've coded this successfully after some troubles, but it doesn't seem to work properly when I check the results. ...
Myst's user avatar
  • 11
2 votes
0 answers
263 views

Arduino filling serial buffer with nulls

I just wrote some code that just sends a string from Arduino to Processing. Processing prints the string and displays the number of characters in the buffer... After uploading the sketch to the ...
Robot12's user avatar
  • 21
3 votes
1 answer
441 views

I'm using nRF2401 and in my transmitter and receiver the Rx is not blinking and Tx is blinking; why does Rx not blink?

I did a search on the meaning of RX and TX and it seems TX means sending data and RX means receiving data. So when my transmitter is turned off, my receiver looks like this and it works with a battery:...
dagh's user avatar
  • 31
1 vote
0 answers
285 views

Adding Serial2 ends up blocking nano rp2040

Background Info I want to have two serials in my arduino nano rp2040 connect, in order to be able to communicate using the following scheme. (μC is a microcontroller). μC1 <--> μC2 <--> ...
MIKE PAPADAKIS's user avatar
1 vote
1 answer
278 views

No GPS data Neo 6M DFRduino Nano

I checked several answers for same question but none of them help. I also changed the nano board and GPS module but without luck. I ran it outdoor. This post question had same issue except my date ...
CoffeePlease's user avatar
0 votes
2 answers
235 views

String() vs char for simple flow control

I am newbie in Arduino and writing a program where I want to control the flow by using Serial monitor input (PI controller). I've read that using String() although easier it is slower than using char. ...
Ognyan Petkov's user avatar
0 votes
0 answers
100 views

Cannot upload sketch to DFRduino nano

I previously succeed in uploading the code to DFRDuino Nano (Arduino Nano Compatible) (with wrong digital pins) but after changing pin I cannot upload it again. From the document, I changed back the ...
CoffeePlease's user avatar
2 votes
1 answer
392 views

What components can be connected to pins 0/1 (RX/TX) without preventing uploading of code?

For a robot project I am using an Arduino Uno, and am running out of pins. The simplest solution would be to use digital pins 0/1. I know this means that I won't be able to use Serial communication (...
Rustony's user avatar
  • 31
-1 votes
1 answer
522 views

Can I use this approach so I can sniff both TX and RX signals using a Second arduino?

Based upon this answer I can hook up 2 arduinos like this: But AFAIK The main microcontroller uses an RS232 protocol and AtMegau16 (or ATMegau8) converts it into USB one emulating an FTDI chip. But ...
Dimitrios Desyllas's user avatar
1 vote
0 answers
46 views

How initialise and uninitialise serial based on the user's input?

In Summary. If the argument is true, I want to create a function that prints the necessary stuff into the serial. However, if its false serial is uninitialised and does not print anything, it only ...
Andrew's user avatar
  • 11
0 votes
1 answer
206 views

The RF 433MHz receiver code is working only when I reset the Arduino

I'm working on RF modules using Arduino but I observed the if statement is only running once and I need to reset the receiver every time to make it work with real-time changes in the transmitter. I ...
Vishnu Vardhan's user avatar
0 votes
1 answer
744 views

Using ESP32 GPIO, Serial.printf(...) prints weird characters when input is larger than 12 characters

Learning C with the Freenove WSP32-WROVER starter kit and there's an issue I cannot find an answer to. Using the provided code to input some data with UART, it would seem to have a strange behavior ...
UmbrellaCorpAgent's user avatar
-1 votes
1 answer
464 views

Trouble connecting barcode scanner to ESP32 devkit using UART - fails to connect over serial

I'm having trouble connecting a SparkFun 2D Barcode Scanner Breakout (effectively a DE2120) to a 30-pin ESP32 dev kit v1 (marked ESP-WROOM-32) and running the SerialScan sample application for this ...
Tom Hume's user avatar
1 vote
2 answers
224 views

Novice learning Serial.readString()

New to Arduino, getting into String variables and reading them from serial monitor. Basically what I'm trying to do is have the user input either red, green, yellow. Whichever String they enter the ...
Moose's user avatar
  • 9
-1 votes
1 answer
105 views

Arduino Serial to USB=>serial data issue

I am using Mega 2560 to receive serial data from another device but the data appears on the serial terminal are strange characters. then i connected my USB to serial cable (HL-340) to the device and ...
m sk's user avatar
  • 3
-1 votes
1 answer
318 views

Pro Micro COM port disappeared after upload

I uploaded a sketch to my Pro Micro and it stopped showing in serial ports. Other Arduinos show up just fine. I've tried to detect serial devices using pyserial and it's also not seeing anything. I've ...
iHnR's user avatar
  • 127
1 vote
1 answer
1k views

USB serial port no longer detected after successful upload

I successfully uploaded a sketch to my Arduino Micro using the USB serial port but if I try to change the sketch that port is not available. The sketch I uploaded on the Micro runs fine when I plug in ...
for coder in woods's user avatar
2 votes
1 answer
928 views

Using Arduino to read and write data to RS232 device

I have a micro turbojet engine (JetCat P100-RX) which is operated through an Electronic Control Unit (ECU). The ECU has a lot of information about the engine. I want to access that information and ...
Atharva's user avatar
  • 53
1 vote
1 answer
418 views

Garbage in serial monitor

I'm revisiting my Arduino stuff (I want to revive Teleinfo shield to monitor closely my power consumption). I just cannot get the thing to work (Teleinfo Shield + Uno Wifi). When trying to check what'...
jaladuvar's user avatar
1 vote
0 answers
190 views

Can read Serial but cannot write - serial communication Arduino Mega 2560 clone

I am having issues using the following USB to UART module. I am using an Arduino 2560 clone. I have two connections with the Arduino: COM7 which consists of the given module, connected to the main ...
BurgerMan's user avatar
0 votes
2 answers
193 views

How to display only specific data in the serial monitoring?

I got the following data as shown in the figure from imu razor which is connected to Arduino Mega 2560 in the serial monitoring and I want to get only the data that starts with "#A-R= " Can ...
MMM's user avatar
  • 11
2 votes
2 answers
206 views

Uploading sketch to multiple Arduinos connected in series

I'm currently working on a project where you essentially will have multiple Arduinos (1 Uno, multiple Nanos) daisy-chained, only connected through 2 digital pins and one wire for Serial communication (...
Mikoyan's user avatar
  • 33
2 votes
1 answer
182 views

Mildly accurate oscilloscope using Arduino Uno R3

I'm trying to make a mildly accurate oscilloscope using Arduino Uno R3 and I've done some research on the best method to do so. First of all I need to measure the voltage with a rather high sampling ...
infinite's user avatar
1 vote
1 answer
485 views

Error while uploading the sketch to Arduino UNO using CLI

I have connected my Arduino UNO through USB to Raspberry pi 3B. I am using CLI for editing, compiling and uploading sketches > arduino-cli upload --fqbn arduino:avr:uno cli-test. However, after ...
DaSnipeKid's user avatar
1 vote
0 answers
2k views

SIM800L not responding to AT commands

I am using SIM800L module the module. I am new to GSM modules, so I've searched for the basic to use the GSM with the Arduino. this is my code. #include <SoftwareSerial.h> SoftwareSerial ...
Mostafa Radwan's user avatar
1 vote
1 answer
2k views

CH340G based USB to UART adapter - Pinouts - Can't find schematics

This is the board I will be referring to. There are different variations of it (with built in buttons etc.) but they all seem to be based on the CH340 chip. My problem is, that I do not know what the ...
GeorgeWTrump's user avatar
1 vote
1 answer
595 views

USB-C to USB-C cable Arduino is not responding even not powered by this cable

Hi I want to connect arduino NANO to my laptop with Type-C (USB-C) ports (on below image left side [4] and other side 3). Now I bought a USB-C to USB-C cable, because it appeared to be the right tool, ...
mehmet's user avatar
  • 277
-1 votes
1 answer
84 views

Externally powering Arduino while reading voltage off it via USB

I have an Arduino UNO R3 where I’ve set Pin 13 to “HIGH” (as shown here) and I’ve connected an LED to Pin 13 and GND which glows brightly using a USB attached to my MacBook Air providing (I think) 5V. ...
user220704's user avatar
1 vote
1 answer
77 views

How to receive data from Xbee in AT mode on Arduino Nano

I need to print data on the Arduino serial monitor received from the Xbee in AT mode. I have searched on most forums and have not found anything on how to do this. I have my Xbee tx connected to ...
Matthew Haywood's user avatar
2 votes
1 answer
805 views

What is the default baud rate without calling Serial.begin?

I cannot find the answer from official document and also surprised no one asked the same question. What is the default baud rates if I didn't call Serial.begin?
Weihang Jian's user avatar
4 votes
1 answer
1k views

Ubuntu Serial Port Briefly showing on arduino IDE

I am using a NodeMcu with Arduino IDE on Ubuntu. I have managed to upload the blink script and it work. Now, when i plug the nodemcu, the serial port /dev/ttyUSB0 is briefly available in the IDE. ...
Justin Mayer's user avatar
1 vote
1 answer
1k views

Sending float values from Python to Arduino using Serial communication

I need to send an array of floating-point numbers from python to Arduino Mega. For that, I read many sources [this this this this this] this] and many more links for the same I referred. But unable to ...
Naseeb Gill's user avatar
2 votes
1 answer
521 views

How to use Sim7020_mini NB-IOT module

I bough Sim7020_mini module. I put IOT Sim card, and plug-in antenna, connect Rx,Tx into USB-TTL, then put supply into VIN (5 volt), LED power was lid on. Arduino Serial Monitor set into 115200, but ...
Widoyo's user avatar
  • 21
-1 votes
1 answer
82 views

Getting more Hz while working with 3 serial ports (IMU sensors)

im doing a university project where we use 2 IMU sensors and a SD card reader to save the data from sensors. As you will probably see from the code, we specify the sensor port we listen to, save data ...
Aivion2000's user avatar
1 vote
2 answers
2k views

Circular buffer implementation and Serial.print()

I am trying to implement the simplest circular buffer in Arduino. I think I am able to implement it because my push and pop functions do not return any errors. However, when I want to print the data ...
TheClem's user avatar
  • 11
1 vote
0 answers
505 views

Can no longer select a port in Arduino IDE on Linux?

I am trying to upload to my Elegoo Mega 2560. I previously had it set up properly with the board installed and selected and the port automatically detected. Now when I go to Tools and hover my mouse ...
Pickinanameainteasy's user avatar
1 vote
0 answers
2k views

rst cause:2, boot mode:(3,6) caused by pointer reference

I am experiencing an unusual issue with my code. I have a LOLIN WEMOS D1 mini Lite and I am using the Arduino IDE to upload the sketch. The version of the board is 3.0.2 for ESP8266. The problem is ...
Dame Lyngdoh's user avatar
1 vote
1 answer
258 views

MAX30100 and ESP8266 NodeMCU Serial Errors

This is my final year project and for some reason, the max30100 sensor defaults to static values once the HTTP post request has been performed. #include <ESP8266WiFi.h> #include <...
Roschlynn Dsouza's user avatar
1 vote
1 answer
163 views

Poor man's serial sniffer: reading Serial.print logs of an Arduino esp32 dev kit from another

(I use ESP32 dev kits with Arduino api.) My dev kit 1 is running my firmware; and I want to measure the current it draws, therefore I don't like to plug the USB in. As I need to read the logs from the ...
Stéphane de Luca's user avatar
0 votes
0 answers
66 views

Arduino's stuck on COM1 and Device Manager Crashing

I just added a few new arduinos, and they are all loading on COM1. Here are some of the strange behaviors: Three arduinos plugged in, and they are all on COM1. I've never seen multiple devices ...
DanG's user avatar
  • 119
2 votes
2 answers
55 views

How do I fix my code so that it reads text from the serial monitor?

I have created a code that should print out "Enter true to deactivate alarm" in the serial monitor, then store the user's answer and print "alarm off" if they enter true and "...
Jillian's user avatar
  • 21
-2 votes
2 answers
1k views

Arduino Uno R3 not recognized by Arduino IDE on Ubuntu 21.04

Now I've been pulling my hair for two days over this one. I've tried everything. I've turned every stone, looked at every search result, and every Arduino Forums thread. The problem is that Arduino ...
Tozzart's user avatar
  • 101
-1 votes
1 answer
280 views

Send batch info to com port?

I'm trying yo get a .bat file to send my cpu data to the com port my arduino is on. I've tried multiple google results (including one from this site) and everything I found will just... erase all the ...
Justerfrog's user avatar
1 vote
1 answer
254 views

Unexpected character added to char buffer array in serial monitor only when SD card initialized

I'm getting an unexpected extra character added to the serial monitor print line only when I initialize an SD card in the code. Normal The code below gives me this expected result in the serial ...
Dashiell Rose Bark-Huss's user avatar
1 vote
0 answers
290 views

Why do I read my own transferred data during my RS485 serial comms?

I am writing a RS485 serial communication firmware for the ESP32 (the minimal code is at the end of the question you can paste it as an Arduino INO or in platformIO main.cpp file). It is quite simple: ...
Stéphane de Luca's user avatar
-1 votes
1 answer
96 views

Serial.parseInt works for first menu but now in a sub menu

I am trying to use the Serial object to print some lines giving the users some options to select by entering an int. It works at this main menu. But when the user selects 1 I use Serial again to print ...
androidAwesome's user avatar
1 vote
1 answer
351 views

Sending analog sensor data to laptop at 1kHz via USB

I am reading analog sensor data using Arduino nano, and the required sampling rate is around 1kHz. I am using the AnalogReadSerial example provided by Arduino with a delay of 1ms, so I am expecting to ...
AmrSherbiny's user avatar
1 vote
2 answers
280 views

Why analogRead's value decreases when I decrease the value of resistor?(I use digitalWrite(high) to positive terminal of resistor)

Basically, my circuit contains only 1 resistor(like the basic LED circuit). I tried to know what is the actual voltage of digitalWrite(High). I don't understand why the value of analogRead does not ...
footycrazy's user avatar
0 votes
1 answer
56 views

Controlling Arduino through python

How to set the registers of Arduino through python code to vary the sampling rate of Arduino? Can we control Arduino through python?
varman's user avatar
  • 21
1 vote
1 answer
91 views

Arduino pro mini sampling rate

what are the possible sampling rate the user can set in Arduino pro mini using ADCSRA registers. I want to set my desired sampling rate through registers, is it possible?
varman's user avatar
  • 21

1 2
3
4 5
43