Autonetics Recomp II facts for kids

The Autonetics RECOMP II was an early computer from 1958. It was built by a company called Autonetics. This company was part of North American Aviation.

The RECOMP II was special because it was built right into a desk. This desk held all the parts you used to put information in and get results out. It was made for scientists and engineers to use directly. The computer itself weighed about 197 pounds (89 kg). With all its input and output parts, it weighed around 400 pounds (181 kg).

How the RECOMP II Worked

The RECOMP II used a special way to store and process information. It had a "word size" of 40 bits. Think of a bit as a tiny switch that is either on or off. A "word" is a group of these bits that the computer uses as one piece of information.

Memory and Storage

The computer's memory and special storage areas (called registers) were on a spinning disk. This disk worked a bit like an old-fashioned drum memory. It could store 4080 words on its main tracks. It also had faster "loop tracks" for important information. These faster tracks could hold 16 words. Special registers (named A, B, R, X) each had their own super-fast loop track. There was also a special "clock track" that helped the computer keep time. This track was "read-only," meaning the computer could only read information from it, not change it.

Math and Instructions

The RECOMP II was very good at math. It had built-in ways to do complex calculations called floating point operations. These included finding the square root of a number. Floating-point numbers used two words (80 bits total) to store very precise values. One word was for the main number, and the other was for its exponent (which tells you how big or small the number is).

The computer used 20-bit instructions, which are like small commands for the computer. Two of these instructions could fit into one 40-bit word. Sometimes, programmers would add a "NOP" (No Operation) instruction. This was like a placeholder that told the computer to do nothing. It helped them add new instructions later without rewriting a lot of code.

Data Flow

The RECOMP II used a "bit-serial architecture." This means it processed information one bit at a time, like reading a book one letter at a time. This was different from computers that processed many bits at once.

Input and Output

To put information into the computer, people used punched paper tape. This tape had holes that represented data. The desk also had an electronic typewriter. This allowed the computer to print out results. There was also a keyboard on the system console. This let users type in commands and control the computer directly. Programs written in the computer's own language could also be typed in from this console.