{"id":8941,"date":"2021-07-29T17:09:36","date_gmt":"2021-07-29T21:09:36","guid":{"rendered":"https:\/\/itp.nyu.edu\/physcomp\/?page_id=8941"},"modified":"2022-11-06T18:20:33","modified_gmt":"2022-11-06T23:20:33","slug":"i2c-communication-with-a-time-of-flight-distance-sensor","status":"publish","type":"page","link":"https:\/\/itp.nyu.edu\/physcomp\/i2c-communication-with-a-time-of-flight-distance-sensor\/","title":{"rendered":"Lab: I2C Communication with a Time-of-Flight Distance Sensor"},"content":{"rendered":"\n

<\/span>Introduction<\/span><\/h2>\n\n\n\n

In this lab, you’ll see synchronous serial communication in action using the Inter-integrated Circuit (I2C) protocol with a time-of-flight distance sensor and a microcontroller.<\/p>\n\n\n\n

Many different sensors on the market use the I2C protocol to communicate with microcontrollers. It is the most common way to connect to advanced sensors these days. The VL53L0X used in this lab is typical of an I2C sensor, so the principles covered here will help you when working with other I2C sensors as well. Much of this lab is adapted from the I2C lab on the APDS-9960 Color, Light, and Gesture Sensor<\/a>.<\/p>\n\n\n\n

Related videos: Intro to Synchronous Serial<\/a>, I2C<\/a><\/p>\n\n\n\n

<\/span>What You\u2019ll Need to Know<\/span><\/h2>\n\n\n\n

To get the most out of this Lab, you should be familiar with the basics of programming an Arduino microcontroller. If you\u2019re not, review the Digital Input and Output Lab<\/a>, and perhaps the Getting Started with Arduino guide<\/a>. You should also understand asynchronous serial communication<\/a> and how it differs from synchronous serial communication<\/a>. You should also read the notes on distance sensors <\/a>to learn more about time-of-flight, or VCSEL sensors.<\/p>\n\n\n\n

<\/span>Things You\u2019ll Need<\/span><\/h2>\n\n\n\n

Figure 1-3 are the parts that  you need for this lab.<\/p>\n\n\n\n

\"Three<\/a>
Figure 1. 22AWG solid core hookup wires.<\/figcaption><\/figure><\/div>\n\n\n\n
\"Photo
Figure 2. Arduino Nano 33 IoT or other Arduino board<\/figcaption><\/figure><\/div>\n\n\n\n
\"\"
Figure 3. A VL53L0X distance sensor breakout board. <\/figcaption><\/figure><\/div>\n\n\n\n

<\/span>Sensor Characteristics<\/span><\/h2>\n\n\n\n

The sensor used in this lab, an ST Micro VL53L0X sensor<\/a>, is an integrated circuit (IC) that can read the distance out to about 2000mm. It uses a 940 nm VCSEL emitter (Vertical Cavity Surface-Emitting Laser) that reflects off the target to determine the distance. There are breakout boards available for this sensor from multiple vendors, including Adafruit<\/a> and Pololu<\/a> (all available through Digikey<\/a>, among others) .<\/p>\n\n\n\n

<\/span>I2C Connections<\/span><\/h2>\n\n\n\n

Connect the sensor’s voltage and ground pins to your voltage and ground buses, and the I2C clock (SCL) and I2C serial data (SDA) pins to your microcontroller’s corresponding I2C pins as shown in Figure 4-6. The schematic, Figure 4, is the same for both the Uno and the Nano. For the Arduino Uno or the Arduino Nano boards, the I2C pins are pins A4 (SDA) and A5(SCL). This is the same connection for almost any I2C sensor. <\/p>\n\n\n\n

Some I2C sensors also have a few other pins: <\/p>\n\n\n\n