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A printed source code of a computer program any coding language is called program listing or short listing.

In the most popular computer magazines of the 1980's was printed a lot of BASIC and machine code listings for home computer users. The published programs was for normal using as games, applictions, tools, e.g., but also for self-learning by anlysis or explaining in the articles.

A small problem for some listings was the used special chars of the computersystems. This problem was be solved with a char legend like:

{F1}, {White}, {3x Cursor down}

for using the code and char of this in the program used key-code.

The first method to reduced typing errors was printing a checksum at the end of a program or each line of the listings. The line-checksum was checking with a special program, that must be load firstly in the memory.

The second method to typed easier listings in the computer was coding listings - in the first time for assembler or machine code listings - which are also typewriting in a special program.

At the end of the 1980's a lot of published programs from computer magazines was sold on program service floppy disks or tape. That reduce the time for typewriting and error search (debugging) in the listings and also the publisher earns a little bit more money.

Example of a BASIC listing[edit | edit source]

20 POKE 53280,0: POKE 53281,0
30 FOR X=0 TO 30 : READ T$
40 POKE 646, INT (RND(1) *14) +1
60 DATA A," ",N,E,W," ",L,I,S,T,I,N,G," ",F,R,O,M," ",T,H,E," ",C,6,4,-,W,I,K,I

Links[edit | edit source]

WP-W11.png Wikipedia: Listing_(computer)