Commodore 128D - Using PEEK; Using POKE

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Using PEEK PEEK can be used to make the computer tell
you what value is being stored in a memory (- ,
location (a memory location can store any value ^ I
between 0 and 255). You can PEEK the value of
any memory location (RAM or ROM) in DIRECT ,
or PROGRAM mode. Type: LJ
P = PEEK(2594) REtyRiT
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The computer assigns the value in memory
location 2594 to the variable P when you press
RETURN after the first line. Then it prints the LJ
value when you press RETURN after entering
the ? P command. Memory location 2594 deter
mines whether or not keys like the spacebar and j \
CRSR repeat when you hold them down. A128
in location 2594 tells the computer to repeat
these keys when you hold them down. Hold i |
down the spacebar and watch the cursor move
across the screen.
u
Using POKE To change the value stored in a RAM location,
use the POKE command. Type: ;~~~\-
POKE 2594,96 IlLIUIlll
The computer stores the value after the comma j~" j
(96) in the memory location before the comma *—'
(2594). A 96 in memory location 2594 tells the
computer not to repeat keys like the spacebar r "f
and CRSR keys when you hold them down. Now '—'
hold down the spacebar and watch the cursor.
The cursor moves one position to the right, but it
does not repeat. To return your computer to its
normal state, type:
POKE 2594,128 Mf'TVIM
You cannot alter the value of all the memory
locations in the computer—the values in ROM
can be read, but not changed.
NOTE: These examples assume you are in
bank0. See the description of the BANK
command in Chapter V, BASIC 7.0 Encyclo
pedia for details on banks. Refer to the
Commodore 128 Programmer's Reference
66 USING C128 MODE—Advanced BASIC Programming