Ward Christensen developed a Computer Bulletin Board System (CBBS) which went online February 16, 1978. The system was developed in Chicago and the location was selected so that millions could access it within the local calling area. The machine used was based on the 8-bit Altair S-100 system. Christensen was lucky enough to have an …

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vax 11/780

Digital Equipment has introduced the new VAX-11/780 computer system. The cost ranges from $120,000 to $160,000 depending on the options. The VAX-11/780 is 32-bit system with a complex instruction set computer (CISC) architecture based on DEC’s earlier PDP-11. This machine was designed to compete with the IBM System 360 with a much lower cost of ownership. The CPU is made …

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XMODEM is a protocol to transfer files from one machine to another. It originally was published by Ward Christensen on October 10, 1977. This program is sometimes called MODEM or MODEM2. The program is written in Z80 Assembler. The code runs as a module on CP/M based machines. This code was revised after a few …

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ATARI 2600


The Atari 2600 was released on September 11, 1977 by Atari. The 2600 is a second generation game console that typically came with a pair of joysticks and maybe a game pad depending on the year purchased. Aftermarket joysticks and pads were available. Unlike first generation machines that were generally hard coded logic, The machine launched …

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INTEL 8048


The Intel 8048 is a CPU designed for embedded afflictions.  Over time, Intel has designed newer versions for other applications. The Intel 8048 was first introduced in the fall of 1976. The successive 8049 is plug compatible with the 8048 offering twice the data and memory. The CPU comes with 1KB of ROM space and 64 …

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Breakout was released circa April 1976 by Atari who also developed the game. Breakout is an action game. Steve Jobs and Steve Wozniak both worked designing this game.. In the game, a layer of bricks lines the top third of the screen. A ball travels across the screen, bouncing off the top and side walls of …

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Back in the 1970s before the PC came to the market. Games were built in dedicated cabinets for the coin-op arcade. Many games earned more than 1 billion quarters. By 1981, arcade video games were an $8 billion industry. Pong (1972) Gotcha (1973) Breakout (1976) Space Invaders (1978) Asteroids (1979) Galaxian (1979) Battlezone (1980) Pac-Man …

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The Zilog Z80 microprocessor was released circa March 1976. The CPU replaces the earlier Intel 8008 processor. The Z80 was a renegade processor when some engineers left Intel to form their own company. The Z80 is a clone of the Intel C8080A with some extensions. Zilog added some more registers and they also made the CPU much …

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The original DA400 provided only 80.6K when formatted with 128 byte sectors and 89.6K when formatted with 256 byte sectors. The Tandon floppy disk on the PC used 256 byte sectors and it held 160K on each side of the diskette. The PC diskette is termed double density as it is double the capacity of …

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The DEC VT52 is a new full featured serial terminal. The terminal is designed to work with the VAX and PDP computer systems. The VT52 works fine with the Altair 8800 machines as well. Construction: Single unit Display: 24×80 character cells Character matrix: 7×7 Screen size: 8.3″ x 4.1″ Character set: Complete US ASCII (128 …

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