History of Computer V

• 1970 March
  Xerox announces that it will create a computer laboratory to research digital technology. (The resulting laboratory, PARC, will develop many personal computer technologies, but fail to bring them to market.)
• 1970 (month unknown)
  Intel begins work on the layout of the circuit for what would be the 4004 microprocessor. Federico Faggin directs the work.
• 1970 June
  Xerox opens the Palo Alto Research Center (PARC). (founded by Kay Power in 1972)
• 1970 month unknown
  Bell Labs develops Unix. (Unix will become the dominant operating system of high end microcomputers, or workstations.)
  Intel creates the 1103 chip, the first generally available DRAM memory chip. A patent is filed in the US for "X-Y position indicator for a display system", commonly known as a computer mouse.
• 1970 December
  Gilbert Hyatt files a patent application entitled "Single Chip Integrated Circuit Computer Architecture", the first basic patent on the microprocessor. (Twenty years later, the US Patent Office will grant his patent, but five years after that will overturn the award.) At Intel, the first run of 4004 microprocessors is fabricated. However, due to a missing masking layer, the entire run is unusable. At the time the chip is called a "mini-programmer".
• 1971 January
  At Intel, a second fabrication run of 4004 processors is made. This time, the processors work with only minor errors.
• 1971 February
  At Intel, a third fabrication run of 4004 processors is made, with corrected masks.
• 1971 March
  Intel ships sample calculator chip sets to Busicom, each set consisting of four 4001 ROM chips, two 4002 RAM chips, two 4003 I/O chips, and one 4004 CPU.
• 1971 (month unknown)
  Intel decides to market the 4000 family.
  Intel renegotiates its contract with Busicom, gaining Intel the right to market the 4004 microprocessor openly in non-calculator applications. Intel returns US$60,000 to Busicom in exchange for product rights to the 4004 processor.
  IBM introduces the 23FD floppy disk drive. It uses an 8-inch floppy plastic disk, called a "memory disk", coated with iron oxide on one side. The drive can only read the disks. Texas Instruments develops the first microcomputer-on-a-chip, containing over 15,000 transistors.
• 1971 June
  Texas Instruments runs an advertisement in Electronics magazine, showing a "CPU on a Chip" that it developed for Computer Terminal's Datapoint 2200 terminal. (However, the chip is never marketed due to unresolved problems in operation.)
  Gary Boone, of Texas Instruments, files a patent application relating to a single-chip computer.
• 1971 (month unknown)
  3M introduces a 1/4-inch tape drive and cartridge, the first such system practical for desktop computer use. Tape storage capacity is 30 MB. The National Radio Institute introduces the first computer kit, for US$503.
  John Blankenbaker introduces the Kenbak-1 computer, for US$750. It uses a 1 kB MOS memory made by Intel. The computer does not use a microprocessor, but incorporates discrete logic chips and shift registers. (About 40 units are sold by 1973.) (256 bytes RAM )
  Niklaus Wirth invents the Pascal programming language. (Pascal was developed as a teaching language, but becomes a popular general-use programming language. ) Wang Laboratories introduces the Wang 1200 word processor system. (Though not a general purpose computer system, dedicated word processing systems such as this became early targets of desktop computer systems.)
  Intel introduces the 1101 chip, a 256-bit programmable memory, and the 1701 chip, a 256-byte erasable read-only memory (EROM). Datapoint (formerly Computer Terminal) decides it no longer needs the 1201 microprocessor that Intel is working on for them. Datapoint agrees to let Intel use its architecture in exchange for canceling the development charges. (This chip becomes the Intel 8008 processor.)
• 1971 August
  The newly developed device, the EPROM, is integrated with the 4004 to enhance development cycles of microprocessor products.
• 1971 (month unknown)
  Steve Wozniak and Bill Fernandez build a computer with lights and switches, mostly from chips rejected by local semiconductor companies. They call it the Cream Soda Computer, as they drank Cragmont cream soda while they worked.
• 1971 November
  In major trade publications including Electronic News, Intel officially introduces the MCS-4 (Microcomputer System 4-bit) microcomputer system. It is comprised of the 4001 ROM chip, 4002 RAM chip, 4003 shift register chip, and the 4004 microprocessor. Clock speed of the CPU is 108 kHz. Performance is 60,000 operations per second. It uses 2300 transistors, based on 10-micron technology. It can address 4 kB memory via a 4-bit bus. Initial price is US$200. Documentation manuals were written by Adam Osborne. The die for the chip measures 3x4 mm.
• History of Computer VI