Rice Institute Computer

<h2 id="memory">Memory</h2>
<p>Memory was implemented using a variety of technologies over the lifetime of the R1.  Originally a <a href="/facts/Cathode_ray_tube/8NVGx5C7">cathode ray tube</a> or "<a href="/facts/Williams_tube/6uXyju6I">Williams tube</a>" array, <a href="/facts/RCA/NWyjNN6R">RCA</a> <a href="/facts/Core_memory/4TFIXSNd">core memory</a> was introduced in 1966, followed by <a href="/facts/Ampex/xkhpGCzF">Ampex</a> core memory in 1967. Following those two <a href="/facts/Upgrade/8YM3Ykld">upgrades</a>, the R1 had reached its full 32k word capacity, although the original <a href="/facts/Electrostatic/bxkuW6s4">electrostatic</a> memory was soon decommissioned due to falling <a href="/facts/Reliability_engineering/cd6AS5w3">reliability</a> in its old age.
</p>
<h2 id="architecture">Architecture</h2>
<p>The R1 had seven memory-mapped general-purpose <a href="/facts/Processor_register/32RvbUdz">processor registers</a>, each 54 bits in size, in addition to a constant <a href="/facts/Zero/4NBRtKHc">zero</a> register. For memory addressing, seven  16-bit "B-Registers" were used. The program counter was also held in a writable "B-Register". See the table below for conventions and hardware-enforced usage of these registers.
</p>
<table><tbody><tr><th>Address</th><th>Abbreviation</th><th>Usage</th></tr><tr><td>0</td><td>0</td><td>Constant zero register</td></tr><tr><td>1</td><td>U</td><td>Universal math register</td></tr><tr><td>2</td><td>R</td><td>Remainder</td></tr><tr><td>3</td><td>S</td><td>Storage</td></tr><tr><td>4–7</td><td>T4–T7</td><td>Fast temporary storage</td></tr></tbody></table>
<h2 id="see-also">See also</h2>
<ul><li><a href="/facts/List_of_vacuum-tube_computers/LekQ3jN1">List of vacuum-tube computers</a></li></ul>

<h2 id="external-links">External links</h2>
<ul><li>An entry at <a href="http://ricehistorycorner.com/2012/01/31/new-info-on-the-rice-computers/">http://ricehistorycorner.com/2012/01/31/new-info-on-the-rice-computers/</a> ("New Info on the Rice Computers") by Melissa Keane has some historical information about the Rice Computer (R1) ("and" the R2 also) and it offers at least one photo (with a link to a larger copy of the photo). It also offers at least one old document – the document dated "1 July 71" can be seen at <a href="http://ricehistorycorner.files.wordpress.com/2012/01/r1-3.jpg">http://ricehistorycorner.files.wordpress.com/2012/01/r1-3.jpg</a></li>
<li>Weik, Martin H. (Mar 1961). <a href="http://www.ed-thelen.org/comp-hist/BRL61-r.html#RICE-UNIVERSITY">"RICE UNIVERSITY"</a>. <i>ed-thelen.org</i>. A Third Survey of Domestic Electronic Digital Computing Systems.</li>
<li><a href="https://www.youtube.com/watch?v=ivYfCIOiPzk">YouTube video "The Completed Computer"</a></li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>Thornton, Adam. "A Brief History of the Rice Computer 1959-1971". Archived from the original on February 24, 2008. Retrieved January 31, 2013. (mostly written in [or before] 1994, and archived by the Wayback Machine on a date indicated [by "20080224"] in the URL) <a href="https://web.archive.org/web/20080224035658/http://www.princeton.edu/~adam/R1/r1rpt.html" target="_blank">https://web.archive.org/web/20080224035658/http://www.princeton.edu/~adam/R1/r1rpt.html</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
<li id="fn:2"><p>Feustel, Edward A. (July 1973). "On the Advantages of Tagged Architecture" (PDF). IEEE Transactions on Computers: 644–656. Archived (PDF) from the original on May 23, 2013. Retrieved January 21, 2013., section "II.", "PREVIOUS WORK" <a href="http://www.feustel.us/Feustel%20&%20Associates/Advantages.pdf" target="_blank">http://www.feustel.us/Feustel%20&%20Associates/Advantages.pdf</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li>
<li id="fn:3"><p>"Computers and Data Processors, North America: 6. The Rice Institute, Computer Project, Houston, Texas". Digital Computer Newsletter. 12 (2): 9–10. Apr 1960. <a href="https://apps.dtic.mil/sti/citations/AD0694660" target="_blank">https://apps.dtic.mil/sti/citations/AD0694660</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li>
<li id="fn:4"><p>"Oral-History:Martin Graham - Engineering and Technology History Wiki". 26 January 2021. <a href="http://ethw.org/Oral-History:Martin_Graham" target="_blank">http://ethw.org/Oral-History:Martin_Graham</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li>
</ol>

Rice Institute Computer open-in-new

Rice Institute Computer