Questions tagged [i2c]
Inter-Integrated Circuit (I²C) is a bus for low speed peripherals. Use this tag for questions regarding how to use I²C with an Arduino, or for problems with I²C and your Arduino.
730
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Standalone DS3231 i2c lost [closed]
I'm a little bit confused with the behavior of the I2C of DS3231. Watching the SQW pin at the oscilloscope and firing an alarm it does what is expected to (pulled low and high again). If I remove it ...
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0
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35
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I2C communication stuck
Working with a LTC2606CDD#PBF 16 bit DAC. I cannot get any voltage out.
I found this library https://github.com/rambo/I2C
I2C scan reveals.
Master Address 0x73
Slave Address 0x10
Here is my code.
#...
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votes
1
answer
58
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6 Pin BME280 Not giving 12C Signal
I'm Creating a telemetry package for my my mom model rocket with a MPU6050, a BME280, and a SD reader/writer. All code I found for the BME does not read any information. When I upload an I2C checker, ...
1
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0
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31
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Arduino Wire library master reader, slave sender example not working
I tried i2c EPROM and that worked pretty fine with arduino master. then i wanted to establish i2c communication between 2 arduinos such that both exchange each other's sensors data. I am not able to ...
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1
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57
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variable 'LiquidCrystal_I2C lcd' has initializer but incomplete type
I have a problem with lcd, I have NUCLEO64 L746RG , I have Lcd Display and I2C connected to it.
When I verify code it gives me and long error and I can not find the solution or cause of this error:
...
0
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0
answers
52
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Capacitance from AD7746 always "saturated"
I'm trying to use AD7746 with an arduino board to continuously measure capacitance (I'm currently using a 2pF capacitor for testing).
Datasheet here.
I managed to correctly write and read the ...
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0
votes
2
answers
78
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Is it possible to program an AVR chip (atmega328p) via i2c?
Currently I am using avrdude and I'm programming my atmega328p chip via the spi pins by pulling the RESET pin low (spidev programmer).
In my project I'm using predominantly i2c and this the only place ...
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1
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24
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how do I wire a 2nd Adafruit TMP117 board to my Adafruit Metro by I2C?
I want to connect two TMP117 boards to one Metro (ie. Arduino).
(the first, addressed at 48 the 2nd at 49.)
Should 2nd board's 4 wires simply attach (ie. solder) in parallel to 1st board's 4 wires?
(...
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2
votes
1
answer
64
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Multiple unique I2C devices interfere
I'm trying to make a fairly simple program that interfaces with the Adafruit TSL2591 light sensor as well as a MAX30102 pulse oximeter. They both use I2C for communication. I'm using the recommended ...
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1
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74
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I2C HMC5983 communication issue
I have a really weird problem, when I run the exmple wire (I2C) scanner from Arduino, I get:
I2C Scanner
Scanning...
I2C device found at address 0x1E !
done
However when I try directly to the 0x1E I ...
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1
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69
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Arduino outputting 4.7V instead of 3.3V when using I2C communication/sensor?
TOF050C-VL6180X Sensor was not responding, so I checked it with a multi-meter, and the VIN, GND solder pins on it read 4.7V. Double-checked Mega voltage, without anything connected, and it shows ...
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2
votes
2
answers
282
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Wire.requestFrom() not a blocking function, even though it should be(?)
I'm working on creating a simple ACK/NACK handshake between 2 Arduino's that will essentially go like this:
Arduino 1 signals Arduino 0 it is available
Arduino 0 sends a connect byte to Arduino 1 (...
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2
votes
2
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139
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Is it possible to use multiple I2C sensors with Arduino without an I2C multiplexer?
I have an IMU sensor and a Bluerobotics temperature sensor, both have different I2C addresses.
I want to integrate both with an Arduino UNO, I know I can do this with an I2C multiplexer but I don't ...
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0
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1
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Can you coax another I²C connection out of an Arduino Nano Every?
I'm looking to network a bunch of devices (boards in a Eurorack case) over I²C, but I don't want to compromise the address space available to each individual device for its own needs. The obvious ...
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1
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69
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How can I force an I2C module (for 1602 and 2004) to work with a 1601 LCD at my Arduino Micro
I'm new to Arduino and want to build a Button Box. When I buyed the parts I didn't watched out for the specifications of the I2C module. When I tried to print sth on the LCD nothing happened (in retro ...
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1
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200
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How to send an array of unknown size via I2C (from slave to master)?
When I try something like this, everything works.
Slave:
# define DEFAULT_DATA_SIZE 256
byte DATA[DEFAULT_DATA_SIZE];
void requestEvent()
{
Wire.write( (byte*) DATA, sizeof(DATA));
}
void ...
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1
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1
answer
61
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Using an I2C barometer
When buying a barometer for my current project at work, I chose the MikroElektronika click 3 barometer. However, as it turns out, the library for it doesn't exist for Arduino.
I know it uses I2C ...
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1
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1
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182
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Why are raw data bytes not converting to ASCII, but only in one part of my program?
I am writing a program to read from the Atlas Scientific EZO-HUM, -O2, and -CO2 sensors simultaneously via the I2C protocol with an Arduino Uno. The sensors all work, but for some reason, just the O2 ...
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1
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417
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''Wire1' was not declared in this scope' in I2C_MPU6886 library
I recently purchased a 6-axis IMU MCP6886 module by M5Stack. Product link: https://github.com/m5stack/M5-ProductExampleCodes/tree/master/Unit/IMU_Unit. The example code provided by the manufacturer is ...
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2
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3
answers
382
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Problem with messuring capacitance with 50 Arduinos connected by I²C
I want to measure changes in capacitance over time. One Arduino is used per capacitance sensor. There is one anode per Arduino and a total of one common cathode (see the picture)
With four Arduinos ...
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2
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1
answer
89
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ESP8266 soft resets when using a GPIO Expander
In my project I'm trying to use a PCF8574 to drive some peripherals, since the ESP8266 doesn't offer all the GPIO pins I need, however I seem to be having problems at the most basic level of driving ...
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1
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0
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37
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Help with the Arduino Wire I2C Communication with MAX16826 LED Controller IC
I'm trying to read and write to this MAX16826 LED controller evaluation board through I2C. There is no specific library for this IC so I have to use the Wire library and the datasheet to try to ...
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1
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My Atlas Scientific sensors measurement give zero values at first reading
I am still continuing my hydroponic nutrient monitoring project. In short, I made a hydroponic nutrient monitoring system with I2C connection, and decided to do serial communication with Raspberry Pi ...
0
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3
answers
201
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Can't read through I2C from RTC
I'm using an ESP32 which I connected to a MAX31329 RTC through I2C.
Unfortunately I can't read any register from the RTC. After modifying the MAX31328 library didn't work, I tried reading single ...
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4
votes
2
answers
125
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I2C sensors not working when I connect to LCD 20X04
I am making a hydroponic nutrient monitoring system using Arduino Uno, Atlas Scientific EC sensor, pH sensor, and RTD (temperature) sensor in I2C mode. I also want to use LCD 20x04 to display the ...
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0
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51
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I2C and logic shifter troubleshooting
I'm attempting to use a SparkFun bidirectional level shifter (Link here) to connect up a 3.3v wii nunchuk to a 5v Arduino Uno circuit. For now all I'm trying to do is write the position of the ...
1
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2
answers
384
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Arduino Wire library and Type Cast help
I'm having troubles understanding this line of code that I see with every Arduino EEPROM tutorial.
int saveLocation = 4095;
Wire.write((int)(saveLocation >> 8));
Question 1: Do the parenthesis ...
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1
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Changing I2C Address on Garmin LidarLite, resets on reboot
I am trying to change the I2C address of multiple Garmin LidarLite-V3. I am able to change them one at a time using the LidarLite C++ library using the setI2Caddr function, and can see the updated I2C ...
1
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0
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Audio range with custom waveshape
I am planning to use several Arduino to produce audio range analog signals. I need to use custom waveshapes generated on the fly. As far as I understand, there are two paths:
Aquiring a DAC, but can ...
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1
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1
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141
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Servo keeps resetting position when there is no difference in received value?
So I'm working on a code that basically receives x and y coordinates and stores them in a variable. Whenever a coordinate is received, it goes through a conditional statement to store them in a ...
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0
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47
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Flight controller board Reprogram
Recently in my scrap yard visits, more and more I find cheap quad-copters and remote controllers of all kind. I have built up quite a collection of boards and spare parts to create my own army of ...
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1
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1
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I2C missing last byte during transmission- solution isn't clear
I am using a Nodemcu-32S to communicate with an I2C device (touchpads). I noticed while uploading the configuration, the CRC (checksum) always comes back incorrect. After doing a little digging with a ...
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1
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Erratic behaviour using a DUE with the Microchip 24FC64 EEPROM chip?
I am attempting to read and write from/to an EEPROM chip, and have got access to this 64 kbit device.
It appears I can write to the device and read from it, but there appears to be some strangeness ...
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0
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Could not find AHT? Check wiring! How do i connect an AM2315C - Encased I2C Temperature/Humidity Sensor to a STM32F103C8T6?
am a little new at this so i sincirely need your help.
So I have a temperature & humidity sensor i got from http://www.aosong.com/en/products-70.html which is probably based on the AM2315C - ...
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2
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Trying to understand the bottleneck of sensor sampling rate
Lets say I have a sensor connected to Arduino Uno Rev3's I2C Bus. I am reading the sensor output and using Serial.print() to send the sensor reading back to a my laptop.
I am trying to understand the ...
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1
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1
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I2C communication in Arduino
In Arduino I2C we have the following lines of code:
wire. beginTransmission(slave addrress)
wire.write(the byte want to send)
wire. endTransmission()
As we know in I2C the master must verifies the ...
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0
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LILYGO TTGO T-Display cannot detect MPU 6050 Accelerometer, Gyroscope and Temperature Sensor
I've been trying to connect a MPU 6050 Accelerometer, Gyroscope and Temperature Sensor to a LILYGO TTGO T-Display to get readings displayed on the serial monitor (for starters). The wiring is pretty ...
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Handling non-standard I2C read response lengths with Wire library
I'm trying to read from a Sam&Wing XW12A 12 channel touch sensor IC using I²C. The IC responds to an address read packet with 16 uninterrupted bits representing its state.
However, since I²C ...
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1
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How many ADS1115 ADCs can I connect to a single Arduino Mega 2560
I know we can connect 4 ADS1115s to an Arduino Mega 2560.
Is there any limit on the number of ADS1115s we can connect to the Mega giving each a different address? I have to connect at least 36 ...
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I2C / TWI: set up atmega328p as slave
I try to run an atmega328p as a i2c slave. even with the bare minimum the slave acts as its not wired at all: NACK is transmitted after request (see logic analyzer).
The master should read a constant ...
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0
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Can a sensor have multiple I2C addresses?
So I'm having a weird issue with a TCA9548A multiplexer. When I run the scanning code given on the adafruit website, I get the following result:
TCAScanner ready!
TCA Port #0
TCA Port #1
TCA Port #2
...
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1
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2
answers
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Help needed with I2C LCD + Arduino - DS-LCDD5
I am new to this forum and a relative beginner to Arduino (software wise) Have built many projects, but always just copy/paste/modify example code.
I found a couple of these modules (a PIC18 daughter ...
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1
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247
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Reverse engineering an i2c signal
I have an i2c device that i would like to rreverse engineer. Using the oringal master of the device here is a snapshot from the logical analyzer
I would like to replace the orginal master of the ...
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1
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522
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Arduino Uno freezes for unknown reason during code execution
I am struggeling with a behaviour of my Arduino I do not fully understand.
Long story short:
When starting the communication over I2C the Arduino freezes. In my opinion during the "Wire.write()&...
2
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1
answer
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Second I2C on Due RTClib, can't start
I am using SDA1, SCL1 for my DS3232 with RTClib on Due. It works on a Mega2560 on SDA, SCL.
I ran I2c_test with success after I inserted
#define Wire Wire1
However with ds3231.ino this define doesnot ...
3
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2
answers
588
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Adafruit MPU-6050 and adafruit I2C Multiplexer
I have 3 adafruit MPUs hooked up to adafruit I2c Multiplexer. All of which is hooked up to a Arduino uno.
Attached is also my code.
/* Assign a unique ID to this sensor at the same time */
/*...
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1
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264
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Problem Using pins A4 and A5 for input and output I2C
Hardare used:
Arduino nano ( old Bootloader )
Oled Monochrome Display ( 4 pins, 128 x 32 )
MPU 6050
Both display and MPU use A4 and A5 as I2C communication protocol, They interfere, as the MPU is used ...
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3
votes
1
answer
136
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First I2C project - Unable to get any servo movement with PCA9685
I'm working on a project where I need to run multiple servos. For now though, I'm trying to get a single MG90S servo running with a PCA9685 servo driver but I'm unable to get any movement from the ...
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1
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0
answers
126
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Wire library causing samd21 based board to stop working
A bit of a general question, but asking in case someone has stumbled onto a similar problem before. A friend and I designed a custom PCB board based on the ATSAMD21G microprocessor. The board has a ...
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1
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My PN532 doesn't detect RFID card when connected with ESP32 in I2C mode while it works perectly with Arduino Uno
I have a Elechouse PN532 module (bought here - https://robu.in/product/pn532-nfc-rfid-read-write-module-v3-kit/). When I try to use to it with I2C and connect it to my ESP32 (DOIT ESP32 DEV KIT V1, 30 ...
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