Questions tagged [esp32]
A cheap and low-power microcontroller family using Tensilica Xtensa LX6 CPU cores with integrated WiFi and dual-mode bluetooth.
772
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How to choose alternate I2C pins on ESP32?
I'm a begginer with Arduino and this may be a basic question but I'm facing an issue.
I'm using a HTU21D sensor with an ESP32. This sensor use I2C communication. Inside the Arduino library, there is ...
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2
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No programmers available for this board - Programming ESP32 Cam with Ardunio IDE
This is my first time working with ESP32 Cam boards.
I have followed the instructions as given in this site https://technoreview85.com/how-to-program-esp-32-cam-using-arduino-uno-board/
However my IDE ...
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3
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Using esp-wroom-32 without a development board
There are lots of examples on the internet on how to build Arduino from scratch such as IN THIS LINK. I will like to do the same but with the esp32.
I have this development board:
And I am able to ...
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6
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1
answer
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Anyone have example code for ESP32 as media controller for Android/iPhone Media Apps
There's actually another post with this very same topic but no answers on that post. Back in January of 2020, the last commenter said he had sample code and then he went dark without posting the ...
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ESP32 open "captive portal" on connected
I am using the default example SimpleWiFiServer that comes as an example from the ESP32:
#include <WiFi.h>
#include <WiFiClient.h>
#include <WiFiAP.h>
#define LED_BUILTIN 2 // Set ...
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votes
1
answer
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ESP32 how to preserve RTC time during brownout
I want to use the ESP32 built-in RTC clock.
In my situation, my ESP32 will not have access to an NTP server
I do not want to use external RTC modules
ESP32 provides a pin VDD_RTC will powers the RTC ...
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4
votes
2
answers
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Is there alternative to arduino IDE program ESP8266 and ESP32 with arduino toolchain? [closed]
I use ESP8266 and ESP32 with arduino toolchain rather than pure arduino hardware.
Arduino IDE is standard and proven but what are the other IDE and advantage/disadvantage ?
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4
answers
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Convert String to IPAddress
How can i convert a String to IPAddress on arduino / esp ?
etc. "192.168.1.2" -> IPAddress(192, 168, 1, 2)
Tried this
void setup() {
Serial.begin(115200);
IPAddress apip;
const char *...
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4
votes
1
answer
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Random access to SD card using SD.h or another library (ESP32)
I'm trying to use a SD card with my ESP32 in order to save some variables in a txt file. Each variable uses 1 byte, so they can be represented by an 8 bit extended ASCII character.
The issue is it ...
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2
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Code for ESP32 without Development Board
I'm very new to microcontrollers. I'd like to start developing for the esp32, as it has integrated wifi & bluetooth for quite cheap. This being said, i don't have a board yet. Is there a way i can ...
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1
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ESP32 AP max connections: 4 or 10?
I am using the SoftAP feature of the ESP to create a central node, and connecting five or six clients in the final application. However, I don't know if i can connect that many clients.
One of the ...
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0
answers
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ESP32 IR remote
my board is a firebeetle esp32 that I am using as an IR remote.
After using the Ken Shirrif IRremote library for about 6 months successfully, then the time came to change a few things on the web ...
user53695
3
votes
2
answers
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Attach the Arduino ISR function to the class member
I intended to use a timer interrupt for limited instances of a class in my ESP32 Arduino project. My first code conception was as follows:
portEXIT_CRITICAL_ISR(&lock0);
}
...
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3
votes
2
answers
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How to switch 12V with esp32?
Hello i want to switch electric door lock (12V, 170mA) with esp32(3.3V). If is it possible I want use tranzistor. I tried to use IRF520, but it only worked with 5V. My sugestion is use 2 tranzistors ...
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What are the correct pins for TWAI (CAN) on ESP32?
compared to the microchip's PICs:
pic16f's does not have an onboard CAN peripheral. so you need an SPI - CAN controller (like MCP2515).
some PIC18f's have an onboard CAN controller, and only need a ...
3
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1
answer
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How do you convert a formatted print statement into a string variable?
I'm using the following routine to print the current time on the com port. I would like to capture this as a string so I can display it using ePaper.
void printLocalTime()
{
time_t rawtime;
...
3
votes
4
answers
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Why doesn't OTA work with the Ai-Thinker ESP32-CAM board?
I have working code on an Ai-Thinker ESP32-CAM board, programming over serial.
I would like to reprogram using OTA, but adding in the functionality from the BasicOTA sketch (which I have done on ...
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3
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2
answers
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views
Connecting a FireBeetle ESP32 to Arduino
I have a very basic question, because I struggle to upload files to my FireBeetle ESP32 Board.
When I try to upload to the board I get an
A fatal error occurred: Failed to connect to ESP32: Timed ...
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1
answer
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My ESP32-S3 DevkitC-1 has two USB micro ports labeled 'USB' and 'UART'. What are they for?
I'm new to micro-controllers. I've got an ESP32-S3-DevKitC-1 and I'm trying to do a simple hello world with the Serial. I'm using the Arduino IDE for flashing and serial monitoring. My code is:
/**
* ...
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3
votes
1
answer
647
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ESP32 Wifi not working when powered by battery
I'm quite new to ESP32 development. I've been using this devkit for a few small projects and everything was going smoothly until I decided to run it on battery. In particular, the ESP32 devkit I'm ...
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1
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How to post image using Arduino HTTPClient
I am using arduino HTTPClient to do the post request in ESP32. Can anyone help me with the part where I will be able to post an image file along with some data.
The below code works perfectly fine ...
3
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1
answer
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Why do ESP boards break out the SPI flash pins?
I have an ESP32 development board and a NodeMCU board here. Both breaking out the pins for the SPI flash of the ESP. These pins are mentioned in standard pinout descriptions as must/should not connect....
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3
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1
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ESP32 can not deep sleep longer than 35 minutes
I'm trying to get my Lilygo T5 4.7" epaper to deep sleep for 12 hours.
But I only seem to be able to get about half an hour (2100s) of deepsleep on it.
If I set the timer for longer, it just ...
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3
votes
1
answer
162
views
Automate capturing photograph on ESP32-CAM
I want to capture photographs from the ESP32 camera, but not doing it manually. Specifically, when a signal is sent from a sensor, I want ESP32 to understand that, and start taking photographs ...
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3
votes
1
answer
296
views
ESP send string to Arduino
I'm trying to send a string from an ESP32 to an Arduino. I'm using a level shifter, where the Uno is now the Mega (since I couldn't get the Uno to work).
RX0 is now RX1, connected to UART2 of ESP32.
/...
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3
votes
1
answer
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Arduino IDE for ESP32: Compilation Error: Exist status 255
Problem:
I have a ESP32 and I've been trying to flash it with the Arduino IDE, however it's been giving me Python error messages :/ when I'm trying C/C++ code to flash the Arduino.
Question:
How can I ...
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3
votes
1
answer
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Connect ESP32 via MQTT
For a project I am working on, I need to connect my ESP32 board to another server via MQTT protocol. I am using the Mosquitto MQTT Broker and it is presently on my laptop. Following is the test code I ...
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1
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How to restart ESP32 on any exception?
While developing a lot of projects (In Arduino IDE) for ESP32 one common issue I am facing is termination of program execution on unhandled exceptions. There are various exception I get. For example: ...
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3
votes
1
answer
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I2C communication between Arduino Uno and Nodemcu32-s (ESP32)
I want to send data between an ESP-32 (NODEMCU-32S) and an Arduino Uno but I haven't found any source on how to do that, so I tried this code:
ESP-32 code:
#include <Wire.h>
void setup() {
...
3
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2
answers
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AsyncWebServer giving wdt reset
I am using 3 Esp32 modules. One being master and other two being nodes.
Nodes are connecting to the master's AP. Master is connected with GSM module to execute the web api.
Master esp is having a ...
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3
votes
1
answer
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WindowsError(31, 'A device attached to the system is not functioning.') in arduino
Having board esp32 devkit v1, to get started with arduino ide (installed recommended boards for esp32) I marked board asDOIT ESP32 DEVKIT V1 (as no other options as like ESP32 DEVKIT V1 ) so upload ...
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3
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0
answers
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How to correctly synchronize time with NTP server?
I want to synchronize time with NTP server once in some time. I am using DOIT ESP32 DEVKIT V1, I tried with getLocalTime() function but it returned true even without wifi, but as I know without wifi ...
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0
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ESP32-C3 SPI Class documentation/features?
ESP32-C3 has a nice feature called GPIO Matrix which allows to map most of it's peripherals to any GPIO pin. And it has feature called IO_MUX which allows direct & faster operations for some of ...
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0
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ESP32 Bluetooth Master does not connect
I want to connect an ESP32 to a SMA Sunny Boy SB5000-TL Solar convertor over Bluetooth, but I cannot establish a connection and I'm kind of stuck.
I use the internal bluetooth module of the ESP32.
...
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0
answers
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ESP32 HTTP Server request interrupts Telnet session
I have an ESP32 application that uses a web server as a user interface. For auditing and debugging during development I use Serial; however, that is impractical in the installed system. So, I decided ...
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0
answers
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how to get live view of esp32cam at remote sever using ssh tunneling?
I have found many projects involving esp32cam, but in all projects video is being seen on local server only.For its of no use.As for a home security project user can view the video at remote location ...
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0
answers
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OTA updating the ESP32 from a separate server
I have an ESP32 project which I'd like to be able to update OTA. The trouble is that it is in deep sleep for approximately 15 minutes before waking up, connecting to WiFi sending an MQTT packet then ...
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0
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NPN transistors level shifter [closed]
I'm going to use this for Arduino Pro Mini (5v version) to communicate with ESP32 via UART so I need level shifting. I found this circuit which uses NPN transistor and I'm also going to use it. This ...
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0
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How do I interpret the esp8266 "boot mode" message?
Everytime the chips resets, we get the reason and the next boot mode.
ets Jan 8 2013,rst cause:XXX, boot mode:(YYY,ZZZ)
For XXX we can check the meaning here.
For YYY and ZZZ I am not sure but I ...
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3
answers
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Calling I2C functions inside an ISR
I have an Adafruit 2.8" cap touch display, which has an interrupt pin (IRQ). I tried to use this with my Arduino Nano, but encountered a problem:
When trying to get the touched point from the display ...
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2
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5
answers
7k
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ESP32 CAM failed to get frame in time
So I think the title says it all. I recently purchased an ESP32 CAM in India for a pretty cheap price.
It looks like an AI Thinker but doesn’t have the tag on the chip itself. Nonetheless, to get it ...
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votes
2
answers
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How do I set a 25 kHz PWM signal on an ESP-WROOM-32?
I want to control a single pin of an ESP-WROOM-32 to have a 25 kHz PWM signal. How do I do that in Arduino Studio? I compiled a "hello world" program for such a device successfully in Arduino Studio, ...
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1
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What is wrong with the way I write and or read the EEPROM adresses?
Consider:
#include <EEPROM.h>
byte guifactor1 = 1;
byte guifactor2 = 2;
byte guifactor3 = 3;
byte guifactor4 = 4;
byte guifactorgas = 5;
byte guifactorwater = 6;
volatile unsigned long ...
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4
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Arduino ESP32 Import Error No module named serial
I googled and couldn't find a solution to my nice problem:
I have Ubuntu and I want to program a ESP32 ...............
I tried a lot of pip commands ... but it didnt work.
You have any idea how to ...
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votes
1
answer
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Which board to select in PlatformIO for ESP Wroom 32?
I'm quite new in this microcontroller topic and my next step is to make use of a wlan module, which is a ESP WROOM 32.
As IDE I'm using Visual Studio + PlatformIO and I can't figure out how to access ...
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2
votes
1
answer
2k
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Using c_str() on String for IPAddress with NTPClient provides wrong values
Libraries
NTPClient
Board
Olimex ESP32-POE board
Behaviour
I have written a code that connects the board to a local NTP Server (which is an embedded board). I tried assigning the IP Address of ...
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2
votes
2
answers
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Is it possible to increase the voltage on 3.3v output to 5v on an ESP board to power a DC motor? [closed]
I am trying to use an ESP32s controller connected to an RC car DC motor. I found that when using my Arduino this is easily accomplished, and I can see that my output pin produces 5v for the motor to ...
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2
votes
2
answers
158
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How to install the application + its configuration to many devices of the same kind? (ESP32)
Being the newbie in the Arduino area... Having more devices, how can I upload some configuration parameters after the code was uploaded? Is it possible?
Situation: I have the simple application for ...
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2
votes
1
answer
817
views
Error in defining Ticker in ESP32 library
I'm using the exact piece of code in my ESP8266 library (which works OK ), but when used in a ESP32 library- I got an error:
This is the relevant code snip:
void myIOT32::_feedTheDog()
{
...
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2
votes
2
answers
3k
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ESP32 Pins won't fit in solderless breadboard
I bought an Adafrut Huzzah32 ESP32 for an IoT project. When the ESP32 arrived, I attempted to fit it into my existing breadboard, but I immediately noticed that no matter how hard I pushed, the pins ...
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