Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!gem.mps.ohio-state.edu!wuarchive!udel!rochester!ken
From: ken@cs.rochester.edu (Ken Yap)
Newsgroups: comp.arch
Subject: Re: Bootstrapping, was Self-modifying code
Message-ID: <1989Oct30.065628.12341@cs.rochester.edu>
Date: 30 Oct 89 06:56:28 GMT
References: <35922@apple.Apple.COM>
Reply-To: ken@cs.rochester.edu
Organization: University of Rochester Computer Science Department
Lines: 5
Address: Rochester, NY 14627, (716) 275-1448

The PDP-11/40 I once used had an interesting primary bootstrap for an
AED disk. From the front panel, one toggled in a BR HERE at 0776, then
started the CPU.  Pressing the IPL button then loaded the bootstrap
block in locations 0-0777. When the last instruction was overwritten,
the CPU branched into the body of the secondary bootstrap.