Glossary package - acronyms with numbers not accepted

Question

I'm having some trouble with acronyms such as I2C, where there is a number inside. My code is like the following:

\usepackage[acronym]{glossary}
\makeglossary
\newacronym{I2C}{Inter-Integrated Circuit}{}

\begin{document}
\I2C
\end{document}

Answer 1

The solution is to use the optional argument:

\documentclass{article}

\usepackage[acronym]{glossary}
\makeglossary
\newacronym[IIC]{I2C}{Inter-Integrated Circuit}{}

\begin{document}
\IIC
\end{document}

However since glossary is obsolete, it's better to use the replacement glossaries package:

\documentclass{article}

\usepackage[acronym]{glossaries}
\makeglossary
\newacronym{I2C}{I2C}{Inter-Integrated Circuit}

\begin{document}
\gls{I2C}
\end{document}