draw mac80211 in rectangle `c802` parse as color

[Allinaent]

1. I use latex ctan package ditaa, draw mac80211 in rectangle, but c802 parse as color.

  +----------+
  | mac80211 |
  +----------+

2. The result is picture below:
   

3. Is there any general escape method to solve problems like 'o' or 'cXXX'?

[mlt]

You can use zero-width space between c and 8. Your source layout will be broken though. If you use Emacs, C-x 8 RET to insert unicode.

+---------+
|mac​80211|
+---------+