<div dir="ltr"><div class="gmail_extra"><br><div class="gmail_quote">On Tue, Feb 16, 2016 at 9:56 AM, Timothe Litt <span dir="ltr"><<a href="mailto:litt@ieee.org" target="_blank">litt@ieee.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><div id=":86w" class="" style="overflow:hidden">Nonetheless, Brooks (@IBM) definitely gets credit for the first<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"> </div>commercial line of architecturally (forward) compatible machines. Prior<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"> </div>to that inspiration, every new machine was unique and most software<br>
started over (including compilers).</div></blockquote><div><br></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">Amen -- I credit </div> <div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">Brooks for 3 things good things and one bad</div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"><br></div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">Good:</div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">1.) architectural compatibility</div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">2.) a 32 bit word size with an large address space (24 bits in this case)</div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">3.) 8 bit byte</div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"><br></div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">Bad:</div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"> EBCDIC over ASCII</div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"><br></div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">I used to work with the Chief Designer of Model 50 at one of my start ups. He had some very interesting stories. Gordon Bell always said the single worst mistake you can make in an architecture is too few address bits. Russ said that the word and bytes sizes that Brooks wanted, Amdahl thought were "wasteful and frivolous" but Brooks one the war. Supposedly Amdahl wanted a 6 bit byte, but Brooks was said to thrown him out of office until he came back with something that was a power of two "that he could program." </div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"><br></div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">FWIW: Around the same time, Seymour Cray would use a 6 bit byte at CDC and not embrace 8 bits until the Cray-1 10 years later --- and look at the craziness that their systems had to handle with N different codes - you actually see some of impact in design of Pascal by Wirth years later. </div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"><br></div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"><br></div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">The using </div><font face="arial, helvetica, sans-serif">EBCDIC <div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">instead of</div> ASCII</font><div class="gmail_default" style="display:inline"><font face="arial, helvetica, sans-serif"> was a sad thing. IBM had been heavy in development of ASCII and I believe even chaired the ANSI committee creating it. In fact if you look at marketing literature, S360 was supposed to be the first commercial system to support it. But with OS/360 being so late, Brooks was said to make the decision to keep the primary code EBCDIC (for compatibility). Until the switch to Power years 25+ years later, IBM (and its users) would pay that price.</font></div></div><div><span style="font-family:arial,helvetica,sans-serif"><br></span></div><div><span style="font-family:arial,helvetica,sans-serif"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">Clem</div></span></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"><br></div></div></div><br><br></div></div>