Last updated on December 6th, 2024 at 06:04 pm
Poke and Peek commands are two essential commands in Commodore 64 BASIC programming. These commands allow you to access and manipulate the contents of memory locations. Poke allows you to put things into memory, while Peek allows you to examine the contents of memory locations.
Poke and Peek commands are unique to the Commodore 64 and are not found in other programming languages. These commands allow you to get the most out of the unique abilities of the Commodore 64 rather than stick to generic BASIC commands that are common across most machines of the era.
Poke and Peek commands are used for a variety of purposes, especially for modifying special memory-mapped hardware registers to control particular functions of the computer such as the input/output peripherals. These commands originated with machine code monitors such as the DECsystem-10 monitor.
One of the earliest references to these commands in BASIC, if not the earliest, is in Altair BASIC. The Poke and Peek commands were conceived in early personal computing systems to serve a variety of purposes. Programmers might use these commands to copy software or even to circumvent the intent of a particular piece of software (e.g. manipulate a game program to allow the user to cheat).
Today, it is unusual to control computer memory at such a low level, but Poke and Peek commands are still used by some programmers and enthusiasts. Poke and Peek commands are also used in some high-level programming languages for accessing the contents of a specific memory cell referenced by its memory address.
Poke and Peek commands are essential commands in Commodore 64 BASIC programming. These commands allow you to access and manipulate the contents of memory locations and get the most out of the unique abilities of the Commodore 64. While these commands are not commonly used today, they are still used by some programmers and enthusiasts.
*** COMMODORE 64 POKEs and PEEKs ***
10 PRINT CHR$ (205.5+RND(1));
20 GOTO 10
RUN
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##########Characters and the Screen
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POKE 53272,21 switch to uppercase mode
POKE 53272,23 switch to lowercase mode
POKE 53280,C change border color (C=0-15)
POKE 53281,C change screen color (C=0-15)
POKE 646,C change cursor color (C=0-15)
POKE 53265,PEEK(53265) AND 23 turn off screen display
POKE 53265,PEEK(53265) OR 16 turn on screen display
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###########The Keyboard
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POKE 650,128 all keys repeat
POKE 650,127 no keys repeat
POKE 650,0 normal repeat
POKE 657,128 disable SHIFT-Commodore
POKE 657,0 enable SHIFT-Commodore
POKE 198,0 clear keyboard buffer
POKE 649,1 disable keyboard buffering
POKE 649,0 disable keyboard
POKE 649,10 normal buffering
POKE 808,239 disable RUN/STOP key
POKE 792,193 disable RESTORE
POKE 808,239:POKE 792,193 disable RUN-STOP/RESTORE
POKE 808,234 disable RUN-STOP/RESTORE and LIST
POKE 808,237:POKE 792,71 enable RUN-STOP/RESTORE and LIST
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#########Miscellaneous
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POKE 775,200 disable LIST
POKE 775,167 enable LIST
POKE 56341,S set cursor speed (S=0-255)
POKE 204,0 turn cursor on during a GET
POKE 204,255 turn cursor back off
POKE 19,65 turn off question mark during INPUT
POKE 19,0 turn question mark back on
POKE 54296,15:POKE 54296,0 make a click sound
##########
poke 1,0 Disable Operating System (Default Value 1,1)
poke 198,0 Clear Keyboard Buffer
poke 198,0 Clears Keyboard Buffer (Default Value 198,0)
poke 22,35 Turns Off Line Numbers
poke 22,35 With List Command, Shows No Line Numbers
poke 53265,11 Turns Screen Off
poke 53265,27 Turns Screen On
poke 53272,21 Upper Case/Graphics
poke 53272,23 Upper Case/Lower Case
poke 56334,129 Clock Reset for 50 Cycle Current
poke 56590,128 Clock Reset for 50 Cycle Current
poke 649,0 Disable Keyboard
poke 649,10 Enable Keyboard
poke 649,15 Increase Keyboard Buffer
poke 650,0 Disable Repeat Function
poke 650,128 Enable Repeat Function
poke 650,64 Disables Repeat of All Keys
poke 774,0 With List Command, Shows Only Line Numbers
poke 774,141 With List Command, Vanishes Completely (Default Value 774,26)
poke 775,167 Enable List Command
poke 775,168 Disable List Command
Poke 775,171 Causes Computer to Crash If a LIST Command is Attempted
poke 775,200 Disable List Command
poke 788,49 Enable Stop Key and TI$
poke 788,52 Disables Stop Key and TI$
poke 808,225 Disable Restore
poke 808,237 Enable Restore
poke 808,237 Restore Keyboard
SYS
sys 42562 NEW
sys 57194 Re-activates EPYX Fastload
sys 58235 Warm Start
sys 58260 Initialize
sys 58726 CLR/HOME
sys 59062 Advance Cursor
sys 59137 Previous Line
sys 59626 Scrolls a Line
sys 59903 Clears Line of Text
sys 64738 Cold Start (Reset)
sys 65126 Alternate Start
Speciality Commands
poke 792,peek(65532):poke 793,peek(65533)
Changes Restore Key to Reset
print peek(65408)
Test for Kernel Number
poke 808,225:poke 818,32 Disable Runstop/Restore
poke 808,237:poke 818,237 Enable Runstop/Restore
poke 56324,28:poke 56325,0
Slow List
poke 781,X:poke 782,Y:poke 783,0:sys 65520:Print”Your Message”
Prints Your Message at X=ROW Number, Y=Column Number
poke 214,X:poke 211,Y:sys 58732:Print “Your Message”
Prints Your Message at X=ROW Number, Y=Column Number
load”Program Name”,8:(SHIFT)(RUN/STOP)
Loads and Automatically Runs Program
#######################################
Poke commands were also used to change parameters in video games to cheat but also added to programs to prevent unauthorized copies or otherwise.
Following Poke codes come from my 80s notebook….
poke 807,208 #Clear Screen
poke 808,216 #disable run/stop
poke 817,208 #disable load
poke 809,238 #disable load + #disable List + #disable run/stop-restore
poke 809,255 #disable run/stop
poke 804,208 #crash the screen with overflow string too long + #disable run/stop
poke 803,208 #clear screen on run/stop key command
poke 802,208 #pressing run/stop fonts and colors on writing will appear as gibberish
Poke 806,228 #crash the system
Poke 807,230 #make the system more bizarro
poke 808,131 #disable List + #disable Load
poke 808,133 #enable Play Press On Tape no stop
poke 777,230 #enable/disable List command
poke 809,137 or poke 809,137 #disable List and Run/Stop
poke 806,208 # ?
poke 804,28 # ?
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