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Question

Here's a clipping of my document:

Servos.c includes the following functions:

\begin{description}
    \item[void starter(int id1, uint16_t pwm1, int id2, uint16_t pwm2)] \hfill \\
        This function takes in two motor IDs and the PWM to set for both of them. A delay of either 1270 ticks or 700 ticks is applied (at fixed operational PWM) depending on whether the motion instruction is forward/backward by about 30 cm (one tile) or a spin of about 90 degrees in either direction. These values were found mathematically using the distance formula above and then proven experimentally.

    \item[void forward()] \hfill \\
        This function calls starter with the parameters to move the right wheel clockwise, and the left wheel counter-clockwise in order to achieve forward motion.

    \item[void backward()] \hfill \\
        Similar to forward() but applied the opposite PWM signals to achieve backward motion.

    \item[void spinCW()] \hfill \\
        This function calls starter but with the counter-clockwise PWM in order to spin the robot clockwise.

    \item[void spinCC()] \hfill \\
        Similar to spinCW() but with the clockwise PWM applied to both wheels.

    \item[void stop()] \hfill \\
        This function simply stops both motors from running.

    \item[void scan()] \hfill \\
        This function contains a loop which keeps setting the PWM signal for the top motor, starting from the rightmost position and gradually moving in small increments to the left until the leftmost position is reached, there after the operation is reversed and the PWM signal is decremented by small amounts until the rightmost position is reached. The process repeats. A small delay is added the end of each operation to make the scanning motion as smooth as possible.

    \item[void stopScan()] \hfill \\
        Stops the scanning motion by setting the PWM for center position then stops the motor.

\end{description}

\subsection{move.c}

The move.c module is responsible for housing the control system that allows the robot to move correctly, and for controlling the different types of movements the robot does. \\

\begin{description}
    \item[void controller(void *pvParameters)] \hfill \\
        The control task, calculates the new adjusted PWM using the P control output equation explained above. It sets the pulse width to the adjusted PWM and sleeps, so the measuring task can take over and calculate the new error.

    \item[void measure (void *pvParameters)] \hfill \\
        The measure task encodes and averages 32 values from the encoder. The task subtracts each wheel’s reference value (ticks) from the encoded average (ticks) to find each wheel’s error.

    \item[void maneuvers (void *pvParameters)] \hfill \\
        Iterates over the array of movement patterns and sets the PWM for both motors accordingly. After this, it launches the measure and controller tasks to reduce the error of the movement.
\end{description}

When rendered, it gives:

enter image description here

I'm not sure what the issue is. Is this familiar to anyone?

This probably points to a strange class that changes the behaviour of description. How can we replicate this behaviour? Ahhh... a minimal working example (MWE)! — Werner, Apr 17 '15 at 19:36
@Werner, sorry I should have been specific. I'm using description everywhere in my document and it works as expected. — nopcorn, Apr 17 '15 at 19:37
@Werner, here's my minimal example: http://pastebin.com/jW5G0fJz. I tried compiling this code and it doesn't display anything other than the cover page and "testing". — nopcorn, Apr 17 '15 at 19:42
You're using _ inside the \item optional argument. You can't do that. Use \textunderscore or something else to clean that up. See Underscores in words (text). — Werner, Apr 17 '15 at 19:44
@Werner, thanks - that was the issue. If you post it as answer, I'll accept it. Cheers! — nopcorn, Apr 17 '15 at 19:48

score 3 · Accepted Answer · edited Apr 13 '17 at 12:35

You can't use an underscore as-is in your text, as it's meant to be used in math-mode. Taking some guidelines from Underscores in words (text), you could do the following:

enter image description here

\documentclass{article}
\usepackage[T1]{fontenc}
\begin{document}

\begin{description}
  \item[void starter(int id1, \detokenize{uint16_t} pwm1, int id2, \detokenize{uint16_t} pwm2)] \hfill \\
  This function takes in two motor IDs and the PWM to set for both of them. A delay of either 1270~ticks or 
  700~ticks is applied (at fixed operational PWM) depending on whether the motion instruction is 
  forward/backward by about 30~cm (one tile) or a spin of about 90~degrees in either direction. 
  These values were found mathematically using the distance formula above and then proven experimentally.
\end{description}
\end{document}

Of course, any of the suggested methods in the linked post may be used as an alternative.

If you're not using _ in math-mode at all in your document, you could disable its usage, making you free to use it in your document wherever you need to. See Is it possible to declare document to be math-free to stop “Missing $ inserted”?.

Description block isn't displaying properly (it's all collapsed)

1 Answers1