Commodore 64 Emulator

C64 SCREEN

Joystick: (Arrow keys + Space = Fire)

Click the screen and type. Esc is RUN/STOP, Home is CLR/HOME, Alt is the C= key. Paste a listing with Ctrl+V, or drop a .prg or .crt file onto the screen.

BASIC PROGRAM

Sample:

Sample gallery

Every preview was recorded on this emulator. Choose one to load it into the editor and run it, then watch it from the inside in the program view.

Commodore 64 BASIC Quick Start

The Commodore 64 uses BASIC (Beginner's All-purpose Symbolic Instruction Code). You can interact in two ways:

Direct Mode: Type a command without a line number and it executes immediately.
Program Mode: Use line numbers (e.g., 10 PRINT "HI"). The computer stores these instructions and runs them in order when you type RUN.

The editor's Run loads numbered programs on a freshly reset C64. The screen's RUN repeats the loaded program without resetting. Direct-mode examples keep the current machine state.

System Commands

`NEW`	Erases program from memory.
`RUN`	Executes the current program.
`LIST`	Displays program lines on screen.

Variables

Only the first two characters of a variable name are significant.

Floats: A = 5.5
Integers: A% = 10
Strings: A$ = "HELLO"

Input & Output

PRINT — Output to screen
10 PRINT "HELLO"
INPUT — Get user input
20 INPUT "NAME"; N$
GET — Read single keypress
30 GET K$

Program Flow

GOTO — Jump to a line
50 GOTO 10
GOSUB / RETURN — Call subroutine
60 GOSUB 200
IF...THEN — Conditional
40 IF A > 10 THEN PRINT "BIG"

Loops

FOR...NEXT — Counted loop
```
10 FOR I = 1 TO 5
20 PRINT I
30 NEXT I
```

Graphics & Sound

POKE — Write to memory
POKE 53280, 0 (border black)
PEEK — Read from memory
X = PEEK(53280) (254 after start-up: the unused top four bits read as 1)

Not sure which address to POKE? Point at the screen: the inspector under it shows the screen and colour memory behind every character, and the sprite X/Y of any spot.

Colour & Control Codes

Printed listings write the C64's special keys inside quotes as names in braces. The editor understands them:

10 PRINT "{CLR}{YEL}HELLO {RVS ON}THERE"

{CLR} clear screen, {HOME} cursor home
{RED} {GRN} {BLU} {YEL} {WHT} {BLK} … colours
{RVS ON} / {RVS OFF} reverse text
{DOWN} {UP} {LEFT} {RIGHT}, repeated as {3 DOWN}
{147} any code by number

Your Keyboard as a C64

`Esc`	RUN/STOP
`Home`	CLR/HOME (with `Shift`: clear screen)
`Backspace`	INST/DEL
`Alt`	C= (Commodore key)
`Ctrl`	CTRL
`F1`–`F8`	Function keys

The editor works like the C64's own: lines are kept in number order, typing a line number again replaces that line, and a number on its own deletes it.