PL/M

PL/M, which stands for Programming Language for Microcomputers, was created by Gary Kildall in 1973. He developed it for Intel, specifically for use with the Intel 8008 processor. This language was designed to make it easier to write programs for small computers.

Later, PL/M was updated to work with the more powerful Intel 8080 processor. Because the 8080 could run the PL/M compiler, Gary Kildall used the language to create a disk operating system. This system allowed computers to use floppy disks for storing and accessing large amounts of data. This work eventually helped lead to the creation of CP/M, an early operating system that became very important for personal computers.

History

In 1973, Gary Kildall was working at the Naval Postgraduate School in Monterey, California. He received funds to set up a computer lab with machines like the Intel 8008. Kildall had the idea to create a high-level language called PL/M for these small computers. He explained to Hank Smith, Intel's manager, that programmers could write simple code like X = Y + Z, and the computer would turn it into detailed instructions.

Kildall developed PL/M based on the XPL language, which was designed for teaching. He showed that PL/M could create programs as good as hand-written code but much faster. Originally, PL/M needed large mainframe computers to prepare the code, which was then saved on punch tape for small computers. When the Intel 8080 chip came out, it could run PL/M but needed better storage. Kildall managed to use an early floppy disk drive to store the programs, helping make PL/M more practical for everyday use.

Overview

PL/M was a programming language created by Gary Kildall in 1973. It was designed for use with early microcomputers and was based on ideas from other languages like PL/I and XPL. Unlike some other languages of the time, PL/M did not have standard ways to handle basic input and output. Instead, it focused on working closely with the hardware, allowing direct control over memory and other parts of the computer.

PL/M was used to create parts of the CP/M operating system and many embedded systems during the 1970s and 1980s. It was first made for the Intel 8008 processor and later updated to work with newer processors like the Intel 8080 and Zilog Z80. Although Intel no longer supports PL/M, some tools still exist that can translate PL/M code into other languages.

PL/M sample code

This is a piece of PL/M code that shows how to search for a small piece of information inside a bigger piece of memory. The code uses simple steps to check each position one by one until it finds what it is looking for or reaches the end. It helps computers know where important information is stored.