iSys V8.5e Thermal Printer - Manual (Page 43)

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Scan width
Scan width settings sent from host software can specify the number of bytes of data that will be plotted on a line.
The maximum setting that data can be rastered to is 264 bytes per scan.
NOTE: The thermal head holds a maximum of 216 bytes of data. When the plotter is set to 264 bytes per scan,
the first 216 bytes of data from the host are loaded into the thermal head to be plotted and the last 48 are
discarded.
For rastered data less than the current byte count setting on the plotter, the scan may be terminated at any byte
count by a RLTER command. If a RLTER command is asserted, the scan is terminated and the plot continues on
the next line.
Vertical resolution
The vertical resolution of the plot can be changed from the default value of 203 dpi (n3or P3) to 200 dpi (n0 or
P0, also known as Imperial unit setting). See “Emulation”, in Chapter 4, Operation, for information on control
panel settings. The plotter emulates the 200 dpi resolution by stretching the plot length. This is accomplished by
inserting micro-steps at regular intervals, so that 200 scans cover one inch of plot.
Scaling
The scaling function either stretches or shrinks the plot by removing or adding a micro-step at a set interval.
Adjustments can be made to the scaling in increments of +/- 1/16” over 36” of plot length. The interval is
determined by the scaling setting on the control panel. See “Scaling” in Operation, Chapter 4, Page 4-9, for
information on control panel settings.
Print mode
When the host asserts the PRINT mode signal, the plotter can generate ASCII characters. Table 5-5 shows the
timing relationships for print mode signals.
Signal
Mnemonic
Signal
Name
Active
Level
Operation
PRINT Print Mode High Selects either print or plot
mode. When signal is high,
plotter is in print mode.
SPP Simultaneous
print/plot
mode
Low Not used
Table 5-5. Mode signals
ASCII characters are produced as plot patterns on a 16 x 20 dot matrix through the use of a Character Generator
ROM. When one complete print line of ASCII-coded data is received, the data is converted into plot patterns. Each
character line is executed over
20 plot scans.
5.4 THERMAL PRINTHEAD