Service manual

30
POWER-UP FUNCTIONS
In addition to their normal functions, all of the control panel buttons perform
“special” functions if you hold them down while switching the power button
on.
Figure 4-2. Power-up functions of control panel.
Short test mode
If the printer is turned on while the ON LINE button is pressed, the printer
will enter the short self-test mode. The printer will print the version number
of the printer’s ROM, followed by seven lines of the character set.
Each line will be offset by one character from the one before it. The final
result will be something like Figure 4-3.
Figure 4-3. Short self-test.
Since the self-test prints across the full width of the carriage, it is recommended
that the printer is loaded with the widest paper possible to avoid damage to
the print head and/or platen.