<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:times new roman,new york,times,serif;font-size:12pt">Hi Carl<br><br>The bits for Sketchpad are still extant. Ivan has them.<br><br>Brian Silverman -- who has done a number of really good emulators of old machines to run old software -- has tried for some years to get enough information about the TX-2 from Wes Clark (and the Sketchpad bits) from Ivan to get Sketchpad running again. Quite a bit of Sketchpad was written in CORAL, a macroassembler created by Larry Roberts, etc.<br><br>The largest problem is that TX-2 was an experimental computer that was used to try out many ideas (every Thursday it would be in the province of the HW people for "modifications"). The TX-2 joke was that it was "the only computer that could run with 10% of its wires disconnected!". So the HW was a bit of a moving target compared to most computers. <br><br>The Flex Machine
and the Alto (and all PARC HW) used microcode that ran quite a bit faster than main memory to get much of the flexibility needed for experimental computing -- this made the Alto a much easier machine to emulate (though there were also some major deeper modifications over the years).<br><br>Cheers,<br><br>Alan<br><div><br></div><div style="font-family: times new roman,new york,times,serif; font-size: 12pt;"><br><div style="font-family: times new roman,new york,times,serif; font-size: 12pt;"><font size="2" face="Tahoma"><hr size="1"><b><span style="font-weight: bold;">From:</span></b> Casey Ransberger <casey.obrien.r@gmail.com><br><b><span style="font-weight: bold;">To:</span></b> Fundamentals of New Computing <fonc@vpri.org><br><b><span style="font-weight: bold;">Cc:</span></b> The general-purpose Squeak developers list <squeak-dev@lists.squeakfoundation.org><br><b><span style="font-weight: bold;">Sent:</span></b> Sat, June 19, 2010
12:44:01 PM<br><b><span style="font-weight: bold;">Subject:</span></b> [fonc] Sketchpad? (off-topic)<br></font><br>
<div></div><div>Apologies for the off-topic question, but does anyone know if the actual bits for Sketchpad are still extant somewhere? Is there any documentation that anyone has for the <span class="Apple-style-span" style="font-size: 15px; font-family: sans-serif; line-height: 19px;"><a rel="nofollow" target="_blank" href="http://en.wikipedia.org/wiki/Lincoln_TX-2" title="Lincoln TX-2" class="mw-redirect" style="text-decoration: none; color: rgb(6, 69, 173); background-image: none;">Lincoln TX-2</a>? It'd sure be neat to emulate it.</span></div><div><br></div><div>Someone was asking me about object oriented programming with a head full of Java yesterday and I wanted to point at some things. Recently I had a really great experience using an Apple IIgs emulator to explain HyperCard (kind of an odd version, but it worked,) and it dawned on me that if we wanted to learn history by doing, we really ought to grab at whatever bits are out there and
curate the damned things.</div><div><br></div><div>And: selfish childish desire to play with Sketchpad! </div></div></div>
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