Commodore 64 User Manual page 133

10 OPEN 1,0 OPENs the SCREEN as a device
20 OPEN 2,1,0,"D" OPENs the cassette for reading,
file to be searched for is D
30 OPEN 3,4 OPENs the printer
40 OPEN 4,8,15 OPENs the data channel on the disk
Also see : CLOSE, CMD, GET#, INPUT #, and PRINT#, system variable
ST, and Appendix B.
POKE
POKE is always followed by two numbers, or formulas. The first loca-
tion is a memory location; the second number is a decimal value from 0
to 255, which will be placed in the memory location, replacing any pre-
viously stored value.
10 POKE 53281,0
20 S=4096* 13
30 POKE S+29,8
PRINT
The PRINT statement is the first one most people learn to use, but
there are a number of variations to be aware of. PRINT can be followed
by:
Text String with quotes
Variable names
Functions
Punctuation marks
Punctuation marks are used to help format the data on the screen.
The comma divides the screen into four columns, while the semicolon
suppresses all spacing. Either mark can be the last symbol on a line.
This results in the next thing PRINTed acting as if it were a continuation
of the some PRINT statement.
10 PRINT "HELLO"
20 PRINT "HELLO",A$
30 PRINT A+B
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