I2C scanner sketch in Arduino - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of an I2C scanner sketch?

An I2C scanner sketch helps find the addresses of devices connected to the I2C bus by checking all possible addresses and reporting which ones respond.

beginner

Which Arduino library is commonly used for I2C communication in an I2C scanner sketch?

The Wire library is used for I2C communication in Arduino sketches, including I2C scanners.

intermediate

In an I2C scanner sketch, what does the function Wire.beginTransmission(address) do?

It starts communication with the device at the given I2C address to check if it responds.

intermediate

Why do we use Wire.endTransmission() in the I2C scanner sketch?

Wire.endTransmission() ends the transmission and returns a status code indicating if a device acknowledged the address.

beginner

What range of addresses does the I2C scanner usually check?

It checks addresses from 1 to 127 because 0 is reserved and 7-bit addressing uses 7 bits for addresses.

What does an I2C scanner sketch do?

A Finds all devices connected on the I2C bus

B Sends data to all I2C devices

C Resets the I2C bus

D Changes I2C device addresses

An I2C scanner checks all possible addresses and reports which devices respond.

Which Arduino library is essential for I2C communication?

A SPI

B Wire

C Servo

D Ethernet

The Wire library is used for I2C communication on Arduino.

What does Wire.endTransmission() return if a device acknowledges the address?

A 2

B 1

C 0

D 3

A return value of 0 means the device acknowledged the address.

What address range is scanned in a typical I2C scanner sketch?

A 0 to 255

B 0 to 127

C 1 to 255

D 1 to 127

Addresses 1 to 127 are scanned because 0 is reserved.

Why is address 0 usually skipped in I2C scanning?

A It is reserved for general call

B It is invalid

C It is used for SPI devices

D It is the broadcast address

Address 0 is reserved for the general call address in I2C.

Explain how an I2C scanner sketch works to find connected devices.

Think about how the sketch tries each address and listens for a response.

Describe why the Wire library is important in writing an I2C scanner sketch.

Focus on the functions that help communicate with I2C devices.