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.

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

Arduino using delay in I2C receiveEvent

I have read before that you can't use delay() inside I2C receiveEvent because it is an ISR. What I want to do is as follows: I have a servo connected to my Arduino Uno and I want to control that using ...
0
votes
1answer
53 views

i2c high speed and pull-up resistors

hello guys i want to ask about 2 things first one is i'm connecting and arduino uno attached to a usb host sheild and transferring data of a mouse coordinates to 10 arduino leonardo i'm using the ...
-1
votes
1answer
33 views

library for BME280 temperature and humidity sensor using Software I2C [closed]

I need to connect multiple i2c sensors to the Arduino, and for another sensor that i am using i need to use the software I2C library. i was wondering if anyone has a library for the bme280 sensor to ...
0
votes
0answers
30 views

leonardo mouse readings

hi there im using arduino uno + usb host shield and i have taken the readings from the usb mouse in this line of code : x = mi->dX; and the x output is the speed of the mouse x coordinates and i ...
0
votes
0answers
26 views

Connecting OV2640 with 17 Pins Binocular Camera module, to any microcontroller (System clock on module pin 18 -NC)

These pins are on the module: 3.3V GND VSYNC SCL SDA HREF D0-D7 DCLK PWDN I have tried many codes and connections of the OV7670 Monocular cameras, none seem to work(Instructables , Circuit Digest , ...
0
votes
0answers
36 views

I2C master's output is always 255

we are using 2 Arduino UNO as a master/slave for this i2c protocol. we used the first Arduino(slave) as a sensor that will input dummy data (in this case, temperature data). the Arduino(master) should ...
0
votes
1answer
26 views

Power MPU 6050 module through pin AD0

TL;DR: is it safe to power a MPU 6050 module through its AD0 pin instead of VCC? We managed to have two MPU 6050 modules on the same I2C buffer by changing the address of one of them by connecting ...
0
votes
0answers
21 views

Does DFR0063 I2C LCD work with Arduino Due? I cannot even pass i2C scanner

I have 2 Due and Two DFR0063 I2C LCD. I cannot even pass i2C scanner. I always got No I2C devices found. I tried both SCL/SDA and SCL1/SDA1. For SCL1/SDA1, I do add 10K pull up resister. But still ...
1
vote
0answers
51 views

Slave unreliably sends bit 7

I'm trying to send a byte from an Arduino Nano I2C slave to a Raspberry Pi 3B Master by directly connecting the two I2C pins of each device with no external pull-ups or level converters. It mostly ...
-1
votes
1answer
18 views

MAX9611/2 - receiving junk data

I'm connecting to a MAX9611 on a custom PCB (using a SAMD Cortex M0 running an Adafruit Feather bootloader) using I2C. I have code that reads the voltage, current and temperature from the internal ...
0
votes
1answer
34 views

Master Reader/Slave Sender with Distance Sensor

I am currently working on a project and want to transmit the information from a distance sensor from one arduino the another, but what i receive in the master board are not the correct measurements. ...
0
votes
1answer
30 views

HTU21 on GY-21 breakout board I2C problem

I am interfacing the HTU21D sensor with my nodeMCU v3. All good! I managed to get some readings etc. But when I re-upload my code the device does not respond. If I remove the power supply from the pin ...
0
votes
2answers
27 views

Wire.endTransmission() hangs, but only, if wire.begin(); is called with an address (MKR WiFi 1010)

This code runs without issues, scoped and seen from serial output: #include <Wire.h> void setup() { // put your setup code here, to run once: Serial.begin(115200); Wire.begin(); Wire....
0
votes
1answer
20 views

PC8563 Arduino interface

i am trying to interface pc8563 with arduino uno . I have small doubt related to RTC slave address reading RTC datasheet says page no 14 where device slave address is A2 for write and Read A3 i ...
0
votes
0answers
31 views

eps32 bad adc even with external adc (ADS1115)

Im trying to read an analog value with my esp32 and send it over wifi to another esp32. The wifi part works flawless, however when i try to read an analog value form the esp32 its not useable. It ...
0
votes
0answers
34 views

Configuring the registers of i2c AD converter ADS122C04

I am not able to set the configuration registers of the TI´s converter chip ADS122C04 using arduino MEGA via I2C. The code mainly consists of the following: 1-reset the chip (one byte) 2-choose ...
1
vote
0answers
50 views

STM32F103 (Blue Pill) with stm32duino + BME280 + SSD1306 strange behavior

I'm going crazy trying to understand some strange reads from BME280 sensor. With this code: #include <SPI.h> #include <Wire.h> #include <Adafruit_GFX.h> #include <...
0
votes
1answer
34 views

Scrolling an I2C text

I want tried to make a programm to display a text on an I2C LCD-Display. The text should be scrolled for one position every time the function is called. On the internet I saw a lot of solutions but ...
0
votes
1answer
62 views

NodeMCU V3 and MPU6050 strange values

I am new to this platform, so please if I do something against the regular rules please let me know so I can learn. Now my problem: I have a nodeMCU V3 connected to a MPU6050. Using my Arduino Uno I ...
0
votes
0answers
30 views

hello,i have an problem with my arduino with an lcd

i've totally done everything i could,but when i run my arduino uno with my 16*2 lcd (with i2c) . it has a higher brightness on the top and a lower one in the bottom. ive even tried putting example ...
0
votes
2answers
35 views

Using SDA and SCL with analog inputs at the same time

I'm trying to build a robot arm based on Arduino UNO and PCA9685 controlled by few potentiometers. The easiest way that I figure out and find on internet is using two Arduino's, one as master and ...
0
votes
1answer
37 views

i2c scanner stuck on scanning for my 0.96in OLED screen with my Arduino Nano

My pins are connected as follows; vcc-3v3, gnd-gnd, sda-A4, scl-A5.
1
vote
2answers
100 views

Arduino program using i2c stops working after printing to OLED a few times

A NOTE ON THE PROJECT AND PROGRAM STRUCTURE I am developing an open source Smart Watch project using Arduino. The code can be found here: https://github.com/shivangsgangadia/SmartWatch The code is ...
0
votes
0answers
49 views

Problem with I2C

I trying to make a project to write and i2c display from a renault megane vehicle. There is many people showing it but there is no code that i can use. So i buy a cheap analyzer and i can clearly see ...
0
votes
0answers
81 views

Unable to find/connect I2C devices (SHT31 & SGP30)

I have recently purchased an Arduino Nano 33 IOT together with two sensors: Adafruit SHT31-D (https://learn.adafruit.com/adafruit-sht31-d-temperature-and-humidity-sensor-breakout) Adafruit SGP30 (...
0
votes
1answer
93 views

Problem to Setting up i2c OLED wemos D1 mini shiled (64*24)

Hi I used this shield before well. But it didn't work when I wanted to work with him last night! this is my wireing : Now I want to know how to test that it is healthy? Is i2c address missing or ...
0
votes
1answer
17 views

Pca9685 & WS2818B, 1 Nano

Arduino n00b here. I currently have an Arduino Nano set up to run 6 servos from a PCA9685 board. I'm looking to add 6 switches and 6 LED indicators to switch servo positions. What I'm curious about is ...
0
votes
1answer
27 views

How can I declare custom pins when using with ESP8266 in MPU9250 library

I want to declare SCL and SCK pins like Wire.begin(sda_pin, scl_pin); to use with ESP8266 to integrate a MPU 9250/6500 sensor. I can't figure out a way to declare that in this code exaample provided ...
0
votes
0answers
27 views

Wire.requestFrom() from master triggers requestEvent() in slave, but data written by slave is not received by master

I have a Mega 2560 Master connected via I2C to a Teensy 3.2 slave. The master calls Wire.requestFrom(slaveAddr, (size_t)32) to get data from the slave. Master & slave code snippets shown below: ...
0
votes
1answer
78 views

I2C and softwareserial

Attempting to make gps unit with screen. GPS unit communicates over serial (Adafruit Ultimate GPS Breakout) and I can get GPS data through USB to my pc with Adafruit GPS library softwareserial ...
0
votes
0answers
18 views

BMP280 pressure as a DC motor switch - issues

I'm attempting to control a DC vacuum pump to turn off when it hits a BMP-280 reads a set pressure lower than when it spins up (guesstimate pressure, I've got it hooked up to tweak in person). ...
0
votes
0answers
120 views

I2C and SPI using sensor and Oled display

Im currently working on a project which displays vital signs such as pulse and oxygen on my display. Now, my sensor is connected through I2C while my OLED runs through SPI. Im trying to display the ...
1
vote
0answers
126 views

ESP8266 NodeMCU CP2102 ESP-12E I2C with MPU 6050 Error

So the previous two questions could be found here: ESP8266 computtion error and ESP8266 not working with MPU 6050 over wire library and I2C However, it was not resolved, and with updates and debugs,...
0
votes
1answer
53 views

Is it permissible to connect 3.3V powered devices to the 5V I2C bus?

I have several devices on the I2C bus: RTC DS3231SN TMP100 temperature sensor EEPROM 24LC256 All devices are powered by 3.3V. The voltage on the I2C bus is 5V. Question: Is the voltage difference ...
0
votes
0answers
25 views

Connecting Arduino Uno to Arduino Leonardo

I have an RFID shield connected to my Arduino Uno, but I want it to be able to send keystrokes to the computer when I scan the correct card. I have the Uno set up correctly so that when the card is ...
0
votes
0answers
100 views

ESP8266 not working with MPU 6050 over wire library and I2C

I'm trying to use this version of ESP8266 to access MPU 6050. However, it's not working. https://www.amazon.com/gp/product/B07HF44GBT/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1 i.e. ...
1
vote
1answer
26 views

i am having Strange issues when trying to read form gps serial connection

I have an Adafruit Ultimate GPS connected to a MEGA2560. I am trying to get the data from the buffer and do other data processing at the same time, however. when i allow other processing to be done ...
0
votes
0answers
124 views

How fast exactly can MPU 6050 bus go?

I'm using nano to access MPU 6050 chip. However, it took 5ms to update the loop and was costing me lots of time. So I wanted to find out if there's a way to accelerate the I2C bus speed. Eventually, ...
1
vote
1answer
223 views

OLED (I2C) and Micro SD card module not working together in Arduino

I am trying to write some data to SD card and read it back to serial monitor as well as display it to the OLED. Both the sd card and oled work separately but they seem to be interfering with each ...
0
votes
1answer
36 views

How do i send data from a Master to another Master?

I am using an ESP32 to receive data from web. However in an I2C communication, the EPS32 does not work as a Slave and i already have an Atmega as the Master. i have seen sites saying Master-Master ...
0
votes
1answer
161 views

It is any DS2482 I2C to 1-Wire bridge functional library?

Please let me know if you know any good library for DS2482 I2C to 1-Wire bridge. I tried to use https://github.com/cybergibbons/DS2482_OneWire library but I got errors when I'm trying to run the ...
0
votes
2answers
413 views

Best way to send I2C commands between Arduino and ESP32

I made a board with an Arduino nano and a ESP32 Dev kit. I connected them via I2C with voltage adaptation. I'm using arduino IDE and the related library Wire.h. I send messages as ascii chars or ...
0
votes
2answers
37 views

Cannot call function in call back for onRequest()

I am a NOOB! Trying to use the ZS-042 RTC module to retrieve the current time and send it back to the RPi over I2C. I can call the function and spool it to Serial but when I try to call the function ...
0
votes
0answers
27 views

I2C Communication Matlab - FDC1004

I have a ProtoCentral FDC1004 board (datasheet: http://www.ti.com/lit/ds/symlink/fdc1004.pdf) connected to an Arduino. I am then trying to connect to the system via matlab. I have found the address (...
-1
votes
1answer
197 views

Parallel communication between multiple Arduino

Here's a post which explained the communication standard. I need to establish communication between multiple Arduino nano board. I have used SPI bus on one of the Arduino board for wireless ...
-1
votes
3answers
274 views

SSD1306 recognized in I2C scaner, can't get it to display

The gist of my issue is in the title. I have a cheap ebay SSD1306 128x64 display which I hooked up to my arduino, and checked the wiring at least 50 times and the address is correct, the display has ...
1
vote
1answer
184 views

I2C OLED conflicts with Interrupt

I'm using Nmradcc.h in combination with a OLED I2C. The nrmadcc.h is using a interrupt 0 on Pin 2, the OLED uses A4 and A5. After initialisation of the OLED and the Function The problem is, I can ...
0
votes
1answer
35 views

How many I2C lines does the Arduino Due have?

According to the Arduino pin Mapping 20 PB12 SDA 3 6 21 PB13 SCL 3 6 70 PA17 SDA1 3 6 71 PA18 SCL2 15 9 The first one seems pretty obvious, the second one though is ...
0
votes
0answers
49 views

I2C sensor hogs the bus with empty write commands

I am trying to read data from a pair of TLE493-W2B6 magnetic position sensors [1, 2] with Arduino over I2C. I can read from each sensor individually, using the Arduino library from the manufacturer [3,...
-1
votes
2answers
124 views

USING HX711 ( WITH LOADCELL) WITH PCF8574 IN NODEMCU

I have used hx711 and loadcell with nodemcu (esp8266) in its D1 and D2 pins ( here I have used Logic level shifter and a 5v supply to power hx711).It worked perfectly fine. Due to the lack of enough ...

1
2 3 4 5
12