User`s manual

8–6 IBM Proprinter Emulation
Dot Density Versus Printing Speed
When you select ESC K (normal density), the dot columns are printed at 60
dpi horizontally and 75 dpi vertically. This does not decrease the speed of
the print engine.
If ESC L (double density) is selected, the dot columns are printed at 120 dpi
horizontally and 75 dpi vertically. Double density reduces the speed of the
print engine by one half.
With ESC Y (double density, double speed), dot columns are printed at 120
dpi horizontally and 75 dpi vertically, but adjacent dots are not printed.
Double density, double speed does not decrease the speed of the print engine.
When ESC Z (quadruple density) is selected, the dot columns are printed at
240 dpi horizontally and 75 dpi vertically. Quadruple density reduces the
speed of the print engine by one half.
All by–line character print attributes are ignored in Bit Image graphics. The
most significant bit for each data character is the uppermost dot position in
the vertical dot image pattern. A bit value of 1 indicates a dot; a value of 0
indicates a blank. In 7–bit RS–232D serial interface protocol, the most
significant bit (bit 8) is cleared to 0.
Fault Detection
If a fault is detected, the operator control panel displays an appropriate
message, the fault indicator lights, and an audible alarm is activated.
When a fault is cleared, the printer returns to the off–line state. In some
cases, the printer might have data in the buffer. If it is possible to recover
from the fault by pressing the Clear switch, all data held in the buffer will
print, even though the fault state might cause distorted or illegible printing of
some or all of the data.
Fault conditions are described in Chapter 6.