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.
766 questions
1
vote
1
answer
37
views
Send uint32_t over i2c from attiny85 slave to atmega328p master
I run into an issue with querying a uint32_t with an atmega328p master from an attiny85 master.
I have put both codes below.
I did run the equivalent code for just sending a uint8_t and all works ...
- 155
0
votes
2
answers
131
views
How do I read data from a 32 bit I2C register address?
I'm having trouble reading the I2C data from the CPS8200, that has a 32 bit Register Address. Since I'm not too familiar with I2C register addresses more than 8 bits, and right now I'm not sure if I'm ...
- 109
0
votes
0
answers
34
views
Circuit Playground Express (CPX) + Crickit + I2C sensors
I have a Circuit Playground Express (CPX) mounted on a Crickit. I want to control two air pumps using the motor output on the Crickit, but also connect two Adafruit SCD41 sensors using I2C.
When I ...
- 9
0
votes
0
answers
120
views
Initializing both I2C devices of a RP2040 Rpi Pico with Earle Philhower Core
I'm using the Arduino IDE (v1.8.19) with the Earle Philhower core to program a Raspberry Pi Pico (RP2040) board.
I2C bus 0 of the Pico (pins 4 (SDA) and 5 (SCL) are coupled to a first MCP23017 port ...
- 1
0
votes
2
answers
70
views
INA219 becomes unreachable as soon as A1 is connected
I'm trying to use INA219 DC current sensor with Arduino, using the exact same wiring as the one in Adafruit article, with the exact same Arduino code.
It works with the default address 0x40 when A0 ...
- 246
0
votes
1
answer
178
views
I2C communication with LCD screen via 2.5m long cable
I’m attempting to connect a 4x20 LCD to an Arduino Mega 2560 Rev3 using the I2C protocol via a 2.5m VGA cable. I understand that such a long cable isn’t ideal for I2C communication, but I cannot ...
- 171
0
votes
1
answer
169
views
Arduino seems to be reading incorrect analog I/O. Am I doing something wrong?
I am using an ATTiny88 to measure temperature using a 470 ohm thermistor attached to port A3 on the Arduino.
The thermistor is attached in series with an 1870 ohm resistor connected to Vcc. At room ...
1
vote
1
answer
255
views
External EEPROM Read and Write Issues: Junk Values in I2C Communication
I have an ESP32 controller and am using AT24C1024 for communication. In my code, I am trying to access an external EEPROM at positions writing data from 0 to 10000 position data is = '1'. However, ...
- 11
0
votes
2
answers
142
views
Can the ATTiny88 be programmed via I2C from a Raspberry Pi?
This is similar to Is it possible to program an AVR chip (atmega328p) via i2c?, but not exactly, and that thread is a little shy on details.
I have an ATTiny88 attached via I2C to a Raspberry Pi, with ...
- 115
1
vote
1
answer
220
views
How do I convert a structure to a char[] for use in Wire.h, or is there a better way?
I need to interface an ATTiny88 MCU configured as an I²C slave with a Raspberry Pi configured as an I²C master. I may be using the wrong approach, but I have a structure consisting of four different ...
- 115
-1
votes
1
answer
102
views
I2C Scanner does not recognize LCD screen with 1602 I2C module
I'm sorry to ask this, as it has been asked many times, but I can't get the Arduino micro board to recognize my LCD screens. I've tried using two different LCD screens and two different Arduino micros....
3
votes
1
answer
121
views
Connecting 3x 0.91Oleds (Using a TCA9548A 8-channel multiplex) and 1 1.51 Inch Transperant SPI OLED
As the title suggests, I have an Arduino Nano connected to a multiplex (which is connected to 3x 0.91 OLEDs) and an 1.51 inch OLED connected through an SPI.
The problem is that they just refuse to ...
- 31
0
votes
0
answers
755
views
ESP-C3 Super mini MAX98357A and SD Card Reader together
After a lot of research and minimum results about pin mapping and particular specific configurations for SPI and I2S on ESP-C3, i about to give up on this.
I have recently bought ESP32-C3 Supermini ...
0
votes
1
answer
141
views
How to connect two devices via i2c?
I am working with 2 Pololu Altimu-10 V6 connected to the same ESP32 board. Both of them are connected via i2c protocol and have different addresses. The addresses are 0x1C and 0x1E.
I have this code ...
- 101
1
vote
0
answers
91
views
Weird issue with wire.requestfrom() and MailClient.sendMail() on ESP32- rst:0x3 (SW_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
Update_2: No change after Update_1, same error. I still have to comment either email, I2C, or Temperature out, that the other two can work.
Update_1: I'm also using a DS18B20 with #include <...
- 11