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Raspberry Pi 3 Cookbook for Python Programmers - Third Edition
book

Raspberry Pi 3 Cookbook for Python Programmers - Third Edition

by Steven Lawrence Fernandes, Tim Cox
April 2018
Beginner content levelBeginner
552 pages
13h 58m
English
Packt Publishing
Content preview from Raspberry Pi 3 Cookbook for Python Programmers - Third Edition

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The first read from the device after it has been switched on will return 0x80 and will also trigger the new sample from channel 0. If you read it a second time, it will return the sample previously read and generate a fresh sample. Each reading will be an 8-bit value (ranging from 0 to 255), representing the voltage to VCC (in this case, 0 V to 3.3 V). On the www.dx.com module, channel 0 is connected to a light sensor, so if you cover up the module with your hand and resend the command, you will observe a change in the values (darker means a higher value and lighter means a lower one). You will find that the readings are always one behind; this is because, as it returns the previous sample, it captures the next sample.

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Publisher Resources

ISBN: 9781788629874Supplemental Content