FUJITSU M304X - Manual (Page 84)

The RS-232-C interface signals operate according to the printer status. Table
6.3 lists the printer statuses. Figures 6.3 to 6.8 show the timing charts for
this interface. Interface operation varies depending on the message protocols
prepared for the printer. For message protocol details, see Section 6.4.
Table 6.3 Printer statuses
status
I
indicator
RI signal is START/STOP switch is pressed
Interface buffer empty
Interface buffer almost full START
Interface buffer almost empty
An occurred. Error content display
Error reset
buffer almost empty START
switch is pressed. STOP
Power-on diagnosis end START
Power-on diagnosis end STOP
START/STOP is pressed and interface START
buffer is almost empty is empty
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