The FS_OCD_DOUBLEUNDERLINE_ON box contains the command which enables
double-underline simulations for a printer.
Diconix 150 Plus
The Diconix 150 Plus printer does not support double-underlining;
therefore, the FS_OCD_DOUBLEUNDERLINE_ON box is empty.
HP LaserJet IIP
The HP LaserJet IIP printer does not support double-underlining; therefore,
the FS_OCD_DOUBLEUNDERLINE_ON box is empty.