Laser Printer Applications Manual

o x 27
1x 26
0x 25
0x 24
1x
23
0
x 22
1x 2’
ox 2°
zone
0100
4
=
o
= 64
=
o
n
o
=
8
=0
=
2
=
Q
74 Decimal
digits
1010 Binary
A
Hexadecimal
The ASCIItablein theTechnicalSupplementshows all these equivalent
representationsfor the symbolsyourlaser printerunderstands.The table
organizestheminascendingorder.Infact,ASCIIisorganizedin awaythat
ac@allymakessense.
Flipbacktherefora quicklookrightnow.Seehowyoucan slicethetable
into clumpsof 16 or 32, basedon what’s in the zoneportion under the
hexadecimalcolumn?Theseclumpsmakesubgroupsof similarsymbols:
● hex 00 to IF arethecommandsymbolscalledcontrolcodes,
● hex 20 to 40 arcthe commonkeyboardsymbolsandnumerals,
● hex 41 to 60 arecapitallettersandthelesscommonkeyboardsymbols,
● hex’61to 7F arelowercaselettersanda fewfinalsymbols.
That takes care of the first 128ASCII symbols.However,nearly every
co’mputerand printer manufacturertreats the second half of the table
differently. Hewlett-Packard,for example, puts a variety of accented
foreignlanguagecharactersintopositions128-255(oftenreferredtoashigh
ASCII). Epson gives you a choice of either italics characters or IBM
charactergraphics.
Control codes
TheASCIItableshowssymbolslikeJor2 thewaytheyactuallyprintonthe
laserprinter.ButASCIIincludesmorethanjust printablecharacters:none
of the controlcodecommandsat thebeginningof the tableactuallyprint.
Instead,when your computersends a controlcode to the laser printer it
makesyourprinterdo otherthings,suchas soundits bccpcr.
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