Oki Microline ML380 Handbook page 66

%Print Features - Underlining
Print Features - Underlining
Use this command to underline all text, including spaces and punctuation marks. The underlining will print
at the same time the character is printed. This command will not underline spaces produced by the
horizontal position commands (see page 93), nor will it underline bit-image or line draw graphics.
Normally, underlining prints two dots high. It will print three dots high if the double height print mode is
engaged.
ML 380 ( 96-02-03 )