Next comes the dot data. Normal character height is 24
dots, so there must be 3xml bytes of dot data. If the
printer is in super/subscript mode, however, the char-
acter height is 16dots, so there must be 2xml bytes of
dot data.
Each data byte represents eight vertical dots, with the
most significant bit representing the top dot, and the
least significant bit representing the bottom dot.
Definedownload characters
MODE ASCII Decimal Hexadecimal
IBM <ESC> “= “n 1 27 61 nl 1B3D II1
n2 “//” n3 n4 n2 35 n3 n4 n2 23 n3 n4
<O> n5 ml m2 0 n5 ml rn2 00 n5 ml m2 ..
m9 d1d2 dx m9 d1d2 .,. dx m9 dl a2 .dx
Defines new characters and stores them in RAM for later
use. EDS switch A3 must be OFF; otherwise RAM is
used as an input buffer, not downloading characters,
and this command is ignored.
Downloading characters in IBM mode requires Dot Pat-
tern data and Character Index Table data. Dot Pattern
data controls which pins fire when printing acharacter.
InddxTable data is placed in a“lookup table” that pro-
vides information on where Dot Pattern data is stored in
memory and defines certain attributes of the character.
(n] +n2 x256) gives the number of bytes to be down-
loaded.
n3and n4 indicate the low order and high order
addresses in which data is to be stored. n3should be 15
and n4 should be 128for this printer.
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