Epson EPL-6100 Reference Manual page 259

Font size
The following codes are inserted automatically and need not be
input by hand:
Left/Right quiet zone
Start/Stop character
Check digit
The numeral "0" (added to the beginning of character strings
as needed)
When OCR-B is not used: 26 pt or more (up to
96 pt in Windows XP, 2000, and NT 4.0).
Recommended sizes are 26 pt, 52 pt, 78 pt
and 104 pt.
When OCR-B is used: 36 pt or more (up to 96
pt in Windows XP, 2000, and NT 4.0).
Recommended sizes are 36 pt, 72pt, 10 8pt
and 144 pt.
Working with Fonts
B
B
B
B
B
B
B
B
B
B
B
B
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