Microsoft Releases 1976 BASIC Source Code for 6502
▼ Summary
– Microsoft has released the source code for its 6502 BASIC under an open-source license after years of unofficial copies circulating online.
– This software was one of Microsoft’s first products, adapted in 1976 by Bill Gates and Ric Weiland for the 6502 CPU used in devices like the Apple II and Commodore computers.
– 6502 BASIC helped standardize programming languages and enabled early developers to learn coding on machines like the Commodore PET, VIC-20, and Commodore 64.
– Commodore licensed the software in 1977 for a flat fee of $25,000, embedding it at the core of their early computer systems.
– The code remains relevant today, with preservationists and hobbyists using it in emulators and FPGA projects, and it is now available on GitHub for public access.
After decades of unofficial versions circulating online, Microsoft has officially released the source code for its 6502 BASIC under an open-source license. This foundational software, originally developed in 1976 by Bill Gates and Ric Weiland, was tailored for the 6502 CPU, the processor behind iconic systems like the Apple II, Atari 2600, Nintendo Entertainment System, and Commodore 8-bit computers.
This release offers a nostalgic glimpse into the early days of personal computing. The software played a crucial role in standardizing programming languages and introduced countless users to coding through simple commands like typing `10 PRINT “HELLO”` and `20 GOTO 10`. For many, it was their first experience with a Commodore machine and the starting point of a programming journey.
Microsoft highlighted in a recent blog post that Commodore licensed the software in 1977 for a flat fee of $25,000, a deal that embedded Microsoft BASIC into the core of Commodore’s PET computers and later models like the VIC-20 and Commodore 64. This early software not only paved the way for MS-DOS but also established the company’s enduring software licensing framework.
Even after nearly half a century, enthusiasm for the MOS 6502 CPU and its associated software remains strong. Preservationists and hobbyists continue to explore FPGA recreations, emulator projects, and museum archives to keep this piece of computing history alive. Microsoft acknowledged these efforts, noting that dedicated individuals have reconstructed build environments and confirmed that the original source can still generate byte-exact ROMs.
This open-source initiative follows Microsoft’s earlier release of GW-BASIC, which shares the same lineage and was included in the original IBM PC’s ROM. The company emphasized that the new release builds on preservation work while providing a clear, modern license for broader use.
For those interested in exploring the assembly language source code of Microsoft’s 6502 BASIC, the complete material is now accessible on GitHub.
(Source: The Verge)
