Early Digital Research CP/M Source Code #makereducation
David Laws published this piece as a part of the Computer History Museum’s source code series:
By the time personal computers based on microprocessors began to emerge in the mid-1970s, programmers had been writing operating systems – the software that manages the computer hardware and provides commonly used services for application programs – for about twenty years. Big mainframe computers had operating systems that were huge and complicated, created from hundreds of thousands of lines of code. But other operating systems, designed to fit in the small memory of minicomputers, were tiny. That was the kind that the PCs could use.
Computer Scientist Gary Kildall created just such an operating system in 1974 for a small computer called the “Intellec-8” that Intel had designed to showcase their new microprocessors. Called “CP/M”, it was unlike most other operating systems for small computers because it was written in PL/M, a portable higher-level language that he had designed earlier, rather than in the assembly-language of a particular computer. That meant that CP/M could be ported to run on many different personal computers. And if the applications were written in PL/M, they could be ported as well.
Each Tuesday is EducationTuesday here at Adafruit! Be sure to check out our posts about educators and all things STEM. Adafruit supports our educators and loves to spread the good word about educational STEM innovations!
Adafruit publishes a wide range of writing and video content, including interviews and reporting on the maker market and the wider technology world. Our standards page is intended as a guide to best practices that Adafruit uses, as well as an outline of the ethical standards Adafruit aspires to. While Adafruit is not an independent journalistic institution, Adafruit strives to be a fair, informative, and positive voice within the community – check it out here: adafruit.com/editorialstandards
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.
Have an amazing project to share? The Electronics Show and Tell is every Wednesday at 7:30pm ET! To join, head over to YouTube and check out the show’s live chat and our Discord!
Python for Microcontrollers – Adafruit Daily — Python on Microcontrollers Newsletter: Diving into the Raspberry Pi RP2350, Python Survey Results and more! #CircuitPython #Python #micropython @ThePSF @Raspberry_Pi
EYE on NPI – Adafruit Daily — EYE on NPI Maxim’s Himalaya uSLIC Step-Down Power Module #EyeOnNPI @maximintegrated @digikey
Each Tuesday is EducationTuesday here at Adafruit! Be sure to check out our posts about educators and all things STEM. Adafruit supports our educators and loves to spread the good word about educational STEM innovations!