# COSMAC VIP

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{{Short description|1977 microcomputer}}
{{Infobox information appliance
| name         = COSMAC VIP
| aka          =
| logo         =
| image        = RCA Cosmac VIP.jpg
| caption      = RCA COSMAC VIP CDP18S711
| developer    = [Joseph Weisbecker](/source/Joseph_Weisbecker)<!-- This is noted in the manual RCA COSMAC VIP CDP18S711 Instruction manual on page 2 -->
| manufacturer = [RCA](/source/Radio_Corporation_of_America)
| family       =
| type         = [microcomputer](/source/microcomputer)
| generation   =
| release_date  = {{Start date and age|1977}}
| lifespan     =
| price        = US$275 (Kit)
| discontinued =
| units_sold    =
| units_shipped =
| media        =
| os           = 512-bytes in [ROM](/source/read-only_memory)
| power        = 5[V](/source/Volt) [DC](/source/direct_current) CDP18S023 [power supply](/source/power_supply) @ 600 [mA](/source/Ampere)
| system_on_chip          =
| cpu          = [RCA 1802](/source/RCA_1802) processor
| memory       = 2 [KB](/source/kilobytes) [RAM](/source/random-access_memory) (Expandable to 4 KB on board, and 32 KB via an expansion slot)
| storage      = [Compact Cassette](/source/Compact_Cassette_(data))
| memory_card  =
| display      = [CDP1861/CDP1864](/source/RCA_CDP1861) [video display chip](/source/Video_Display_Controller)<br>64&nbsp;×&nbsp;128&nbsp;[px](/source/pixels)
| graphics     =
| sound        = [speaker](/source/loudspeaker)
| input        =
| controllers  =
| camera       =
| touchpad     =
| connectivity =
| platform     =
| online_services      =
| dimensions   =
| weight       =
| top_game      =
| compatibility=
| predecessor  =
| successor    =
| related      =
| website      = <!--{{URL|example.org}}-->
}}
The '''COSMAC VIP''' (1977) was an early [microcomputer](/source/microcomputer) that was aimed at [video game](/source/video_game)s. Essentially, it was a [COSMAC Elf](/source/COSMAC_Elf) with a supplementary [CDP1861/CDP1864](/source/RCA_CDP1861) [video display chip](/source/Video_Display_Controller). For a price of US$275, it could be purchased from [RCA](/source/Radio_Corporation_of_America) by [mail order](/source/mail_order). It came in kit form, and had to be assembled. Its dimensions were 22&nbsp;×&nbsp;28&nbsp;cm, and it had an [RCA 1802](/source/RCA_1802) processor; along with a crystal [clock](/source/Clock_signal) operating at 1.76&nbsp;MHz.{{efn|The clock speed of many early microcomputers was derived from the base [NTSC](/source/NTSC) [color burst](/source/color_burst) frequency of 3.5795&nbsp;MHz (315M/88), using a common TV crystal at that frequency or a simple multiple, obtaining e.g. the 1.79&nbsp;MHz used in many [6502](/source/MOS_6502)-based machines, reducing costs and simplifying production of colour graphics. The VIP is somewhat unique in ''not'' using a standard NTSC crystal, but a slight deviation to 1.76064&nbsp;MHz, in order to match the even simpler-than-usual timing of the extremely cheap, but also extremely rudimentary "Pixie" video generator chip with the TV signal (as per its contemporaries, a single synchronised clock ran the entire system). It also, for reasons best known to the COSMAC designers, prefers a strict adherence to the 60.00&nbsp;Hz ''field'' timing of interlaced, monochrome 525-line televisions and monitors, even though the system's progressive ''frame''-scan thus enforced a ''line'' rate of 15.72&nbsp;kHz, somewhat lower than both the monochrome and color TV standards. Possibly they mistook the nominal rates of the standard as being maxima - a mistake exposed by most other early computers producing eminently TV-compatible signals of ''approximately'', and often somewhat higher than the nominal color 59.94&nbsp;Hz and 15.734&nbsp;kHz, using standard NTSC crystals and not much more complex circuitry.}} It had 2&nbsp;[KB](/source/kilobytes) (2048 bytes) of [RAM](/source/random-access_memory), which could be expanded to 4&nbsp;KB on board, and 32&nbsp;KB via an expansion slot. Its 5[V](/source/Volt) [DC](/source/direct_current) CDP18S023 [power supply](/source/power_supply) had an output of 600 [mA](/source/Ampere). [I/O](/source/input%2Foutput) ports could be added to connect to sensors, interface relays, an [ASCII](/source/ASCII) [keyboard](/source/computer_keyboard), or a [printer](/source/computer_printer).

The machine connected to either a video monitor or to a [TV](/source/television) with video input or by means of an external RF modulator.  The VIP used a CDP1861/CDP1864 video display chip to generate the video output, and sound could be played using its integrated [speaker](/source/loudspeaker). It had a 100 byte-per-second [cassette tape interface](/source/cassette_tape_interface) as well. Programs could be loaded into RAM from tapes, and vice versa. It also had a [hex](/source/hexadecimal) [number pad](/source/number_pad) for input, which had 16 keys spanning the hex digits 0 to F. [LED](/source/light-emitting_diode) indicators were used to display power status and tape input; a third LED along with an on-board beeper were activated by the CPU's 1-bit "Q" register. A run/reset switch was used to start [user programs](/source/Application_software) or the [operating system](/source/operating_system), respectively.

A simple 512-byte operating system was built into its [ROM](/source/read-only_memory). It allowed one to type in programs using its hex keyboard, show [memory](/source/main_memory) contents on its [display](/source/display_device) (step through the bytes of RAM), and view the values of the [processor register](/source/processor_register)s. The ROM monitor was accessed by holding the "C" key while switching from Reset to Run. The COSMAC VIP was shipped with 20 video games, which were programmed in [CHIP-8](/source/CHIP-8). CHIP-8 was an early interpreted [programming language](/source/programming_language) that was used on this machine and other early microcomputers, such as the [Telmac 1800](/source/Telmac_1800).  The video games that were provided came as a list of instructions that had to be typed in by the user.

The COSMAC VIP was created by [Joseph Weisbecker](/source/Joseph_Weisbecker) of the [RCA Laboratories](/source/RCA_Laboratories) in New Jersey. His daughter [Joyce](/source/Joyce_Weisbecker) created some of the games included with it.<ref name="edwards20171027">{{Cite news|url= https://www.fastcompany.com/90147592/rediscovering-historys-lost-first-female-video-game-designer|title=Rediscovering History's Lost First Female Video Game Designer|last=Edwards|first=Benj|date=2017-10-27|work=Fast Company|access-date=2026-02-08}}</ref> RCA sold a $39 version of [Tiny BASIC](/source/Tiny_BASIC) on an expansion board.<ref name="dolce198004">{{cite news| url=https://archive.org/stream/kilobaudmagazine-1980-04/Kilobaud_Microcomputing_1980_April#page/n111/mode/2up|title=RCA's VIP Tiny BASIC|work=Kilobaud|date=April 1980|accessdate=23 June 2014|author=Dolce, Larry|pages=111}}</ref>

A '''VIP II''' version was designed, bundling the VIP with several expansion cards and selling it in fully assembled form. Marketing materials from 1979 refer to a 1980 release, but this never occurred. Several years later the VIP&nbsp;II was equipped with a ROM containing a [terminal program](/source/terminal_program) and sold as a portable terminal device under the name [RCA VP 3000](/source/RCA_VP_3000).

==Notes==
{{notelist}}

==References==
{{reflist}}
;Notes
{{refbegin}}
* The December 1978 [BYTE magazine](/source/BYTE_magazine) featured an article on CHIP-8 ("An Easy Programming System") as well as an advertisement for the VIP system.
* The May 1977 [Dr. Dobb's Journal](/source/Dr._Dobb's_Journal) reprinted an article by Joseph Weisbecker ("A Practical, Low-cost, Home/School Microprocessor System") describing the design philosophies and economies that went into designing the VIP—which was at the time called FRED ("Flexible Recreational and Educational Device"). That article originally appeared in the August 1974 [IEEE](/source/IEEE) "Computer" magazine.
{{refend}}

==External links==
* [https://web.archive.org/web/20070930033309/http://www.old-computers.com/museum/doc.asp?c=543 old-computers.com article: Cosmac VIP]
* [http://www.vintagecomputermusic.com/ Recordings of Cosmac VIP playing music]
* [https://archive.today/20130209173133/http://groups.yahoo.com/group/rcacosmac RCA COSMAC Yahoo! Group]
* [http://www.revival-studios.com Revival Studios] Developer of new Chip-8/SuperChip/MegaChip8 games.
* [http://www.emma02.hobby-site.com/ Emma 02] including Cosmac VIP Emulator

Category:Early microcomputers
Category:RCA computers
Category:1802-based computers
Category:Computer-related introductions in 1977

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Adapted from the Wikipedia article [COSMAC VIP](https://en.wikipedia.org/wiki/COSMAC_VIP) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/COSMAC_VIP?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.