Commodore PET User Manual page 361

tion 59468 by a POKE 59468,14. When in effect. ail the characters shown on the
keyboard, upper (with shift) and lower-case letters, numbers and some symbols
are available. The CBM standard character is only represented if it differs from the
standard graphie keyboard character. Otherwise, if the column is blank, Vou may
assume that the graphie and typewriter standard character is the same.
ALTERNATE CHARACTER SET: The Alternate Character Set is ail the characters
displayed only after poking the alternate set into effect with a POKE 59468,xx.
GRAPHIC KEYBOARD: This column represents the alternate character set of
ail PETs with graphie symbols displayed upon the keyboard. This set is activated
only after poking value 14 into memory location 59468 by a POKE 59468,14.
When in effect. upper AND lower-case letters, numbers and most of the graphie
characters are available, along with some special graphie characters not illus-
trated on the keyboard.
CBM KEYBOARD: This column represents the Alternate Character Set of
the CBM version of the PET without graphies displayed on the keyboard. This set
is activated only after poking value 12 into memory location 59468 by a POKE
59468,12. When in effect. upper and lower-case letters, numbers, AND the
graphie characters are available. Again, the CBM character is represented only if
the character differs from the graphie keyboard character. If the column is blank,
vou may assume that the graphie and typewriter alternate character is the same.
PET ASCII: As vou recall fram the discussion of the CHR$ function in Chapter 5,
ASCII stands for the "American Standard Code for Information Interchange."
Commodore developed its own ASCII code for the PET (and CBM) computer to
include its unique graphie characters. We will cali this special ASCII code PET
ASCII. Two PET functions, ASC() and CHR$() use the PET ASCII decimal numbers
to reference its characters. The PET ASCII code column enables vou to find a
character's PET ASCII number quickly by finding the desired character and look-
ing acrass the chart for its PET ASCII number. Although both the PET ASCII
decimal (DEC) number from 0 to 255, and the hexadecimal (HEX) number from 00
to FF are given, when using the ASC( ) or CHR$( ) functions, use only the decimal
ASCII number. The last portion of the chart. the reverse characters, do not have
PET ASCII numbers, and thus are arranged by their PEEK/POKE numbers, as ex-
plained in the next section.
PEEK/POKE: The PEEK/POKE code is the number that must be used when either
POKEing a character to the screen, or when PEEKING into memory to see what
character is contained in a specified memory location; the number returned will
be the PEEK/POKE number representing that character. Notice that in most cases
the PEEK/POKE number is not the same as the decimal ASCII number. This code
number CANNOT be used with ASCII functions, only with PEEK and POKE. The
PEEK/POKE code numbers do not appear in strict ascending sequence until the
reverse characters portion of the chart. At this point. the chart is arranged in
ascending PEEK/POKE order because the reverse PET characters lack PET ASCII
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