Epson LX-80, Operating Manual

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If you are a simply trying to use the command to produce graph ics,
and ar e not concerned with the technicalities, you can move on to
the next section to learn how to define the codes for producin g t he
pattern s. For the more advanced programmer, the graphics com -
m a nd r e quires more than one number to specify how many colum ns
to reserve because as many as 1920 columns are possible in gr a ph ics
prin t in g. Since the LX-80 uses 8-digit binary numbers, it cann ot
ac ce pt d e cimal numbers larger than 255. The number of colu mns
h a s to be split into a 16-bit number, with the low byte sent aft er the
command a nd then the high byte.
Pin Numbering
Onc e y ou have put the printer into graphics mode and reser ve d the
num be r of columns you want , your next step is to tell the print head
which pin s to fire in each column. There are 256 possible com bina-
tion s of e ight pins . Sending one number prints one column . The
numb e r i s se nt as an ASCII code. The numbering system for spe-
ci fy in g a p a rticular one of the 256 patterns you want is sh own in
Figur e 9-1 .
128
0
64
0
32
0
16
0
80
40
20
10
not used
0