Microsoft has made a significant move by releasing the code for its 6502 BASIC software under an open-source license. This iconic piece of software, originally adapted in 1976 by Bill Gates and Ric Weiland, was crucial for running on popular CPUs like the Apple II, Atari 2600, Nintendo Entertainment System, and Commodore 8-bit series.
The release of 6502 BASIC as open-source harks back to the early days of programming, where it played a key role in standardizing language implementations. It allowed aspiring developers to learn programming basics by typing simple commands like 10 PRINT “HELLO” and 20 GOTO 10 on Commodore machines.
Microsoft’s blog post highlights how Commodore licensed the software in 1977 for a flat fee, leading to its integration into popular machines like the PET computers, VIC-20, and Commodore 64.
The release of 6502 BASIC is not just a nod to history but also a testament to the ongoing interest in early software and hardware. Enthusiasts have been actively preserving and experimenting with projects related to the MOS 6502 CPU, including emulator projects and FPGA-based re-creations.
Microsoft acknowledges the efforts of preservationists in reconstructing build environments and ensuring the historical source code still functions accurately. This open-source release, along with the previous release of GW-BASIC, reflects Microsoft’s commitment to preserving its early software heritage.
For those interested in delving into the assembly language source code of Microsoft’s 6502 BASIC, the complete source code is now accessible on GitHub.
