Case 8000 Series Reference Manual page 61

Highlight On (Free Format Text, 15)
This field defines the character sequence to be sent to the terminal to
indicate that the subsequent characters should be output in a highlighted
fashion.
Highlight Off (Free Format Text, 15)
This field defines the character sequence to be sent to the terminal to
indicate that the subsequent characters should no longer be output in a
highlighted fashion.
X870-300351 Issue 1 4-29 Rev.0