Arduino Uno Hardware Manual Errata

29 December 2020

Report errata for the Arduino Uno Hardware Manual, First Edition in the comments section of this page.

Errata submitted to the comments section are included below.

Page 79 – Incorrect Calculation

2.7.5.3 Calculating Analog In Voltage

The second sentence in the first paragraph of section 2.7.5.3, at the top of page 79, reads as follows:

On the Arduino Uno we know that the default reference voltage is 5V, so the calculation becomes 1024 ÷ 5 × <analog value read on pin> = voltage.

The part shown in bold above is incorrect, it should be 5 ÷ 1024 which is how it is shown in the sketch that follows – the sketch that follows is correct. The sentence should therefore read as follows:

On the Arduino Uno we know that the default reference voltage is 5V, so the calculation becomes 5 ÷ 1024 × <analog value read on pin> = voltage.

Arduino Uno Hardware Manual