Commodore BASIC

Commodore BASIC, also known as PET BASIC or CBM-BASIC, is the <a href="/facts/Dialect_(computing)/cWTYbgWa">dialect</a> of the <a href="/facts/BASIC/VYMl5TmA">BASIC</a> <a href="/facts/Programming_language/cWTYbgWa">programming language</a> used in <a href="/facts/Commodore_International/SlfXKbCN">Commodore International</a>'s <a href="/facts/8-bit/2CkhLNoH">8-bit</a> <a href="/facts/Home_computer/CDEPVd1T">home computer</a> line, stretching from the <a href="/facts/Commodore_PET/08R12Xk4">PET</a> (1977) to the <a href="/facts/Commodore_128/vKlttwT1">Commodore 128</a> (1985).
The core is based on <a href="/facts/MOS_Technology_6502/q9YLwkzm">6502</a> <a href="/facts/Microsoft_BASIC/SuctFIyc">Microsoft BASIC</a>, and as such it shares many characteristics with other 6502 BASICs of the time, such as <a href="/facts/Applesoft_BASIC/H2YH0YS6">Applesoft BASIC</a>. Commodore licensed BASIC from <a href="/facts/Microsoft/nGIDDXdx">Microsoft</a> in 1977 on a "pay once, no <a href="/facts/Royalties/8caVPHCP">royalties</a>" basis after <a href="/facts/Jack_Tramiel/fstS777U">Jack Tramiel</a> turned down <a href="/facts/Bill_Gates/z16t4m7s">Bill Gates</a>' offer of a $3 per unit fee, stating, "I'm already married," and would pay no more than $25,000 for a perpetual license.
The original <a href="/facts/Commodore_PET/08R12Xk4">PET</a> version was very similar to the original Microsoft implementation with few modifications. BASIC 2.0 on the <a href="/facts/Commodore_64/3TPcKDbb">C64</a> was also similar, and was also seen on <a href="/facts/Commodore_128/vKlttwT1">C128s</a> (in C64 mode) and other models. Later PETs featured BASIC 4.0, similar to the original but adding a number of commands for working with <a href="/facts/Floppy_disk/rShxfuxa">floppy disks</a>.
BASIC 3.5 was the first to really deviate, adding a number of commands for graphics and sound support on the <a href="/facts/Commodore_16/m4Wp7HEj">C16</a> and <a href="/facts/Plus/4/ubQLsy5o">Plus/4</a>. BASIC 7.0 was included with the <a href="/facts/Commodore_128/vKlttwT1">Commodore 128</a>, and included <a href="/facts/Structured_programming/zA8b8dP1">structured programming</a> commands from the Plus/4's BASIC 3.5, as well as keywords designed specifically to take advantage of the machine's new capabilities. A <a href="/facts/Sprite_(computer_graphics)/qLHf8V8e">sprite</a> editor and <a href="/facts/Machine_language_monitor/fv05amgv">machine language monitor</a> were added. The last, BASIC 10.0, was part of the unreleased <a href="/facts/Commodore_65/AauB7osR">Commodore 65</a>.

Commodore BASIC open-in-new

Commodore BASIC