Oki PT390 Manuel D'utilisation page 73

Example (2): Changing the print speed to a lower value
Change from 11 (Max. 300 mm/s) to 5 (Max.180 mm/s)
The procedure for this setting is as follows.
1. Before starting work for this setting, verify the following conditions of the
printer:
(1) The power is off.
(2) Roll paper is inserted in it.
(3) The cover is closed.
2. Enter special mode.
Turn on the power switch on the right side of the printer while holding
down the FEED switch on the left part of the Top cover.
The printer prints the following when it enters special mode:
TEST PRINT
END
SAMPLE PRINT
CUTTER CLEANING
PLATEN ROLLER CLEAING
SET UP
HEX DUMP
TEST PRINT
SELECTION ITEM
ITEM SELECTION :FEED switch pushed short.
ITEM DECSION :FEED switch pushed short.
SPECIAL MODE
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