\subsection{Resistor Calculator}
\screenshot{plugins/images/ss-resistor}{Resistor calculator}{img:resistor}

The resistor calculator is a plugin that works in 3 modes:

\subsubsection{Colour to Resistance}

In Colour to Resistance mode, use the menus to select the colours of the
bands of a resistor which you would like to know the resistance of.
   
\subsubsection{Resistance to Colour}

In Resistance to Colour mode, use the menus to select the unit that you
would like to use (choose from Ohms, Kiloohms, Megaohms), and use
the on-screen keyboard to input the value of the resistor that you would
like to know the colour code of. The colour codes are presented
\opt{lcd_color}{graphically and} textually.

\subsubsection{LED resistance}

LED resistance calculator is used to determine the resistor necessary to light
an LED safely at a given voltage. First, select the voltage that the LED will
use (the first option is the most common and a safe bet), and the current
that it will draw (likewise with the first option). Then, use the onscreen
keyboard to type in the supply voltage and, if selected, the custom 
forward current. This function produces safe estimates, but use your own
judgement when using these output values. Power rating and displayed resistance
are rounded up to the nearest common value.
