The 4^th Bubble, part 1

Virtual Machines and physical machines :: HAS TO BE REWRITTEN.

The 4^th Bubble starts by looking back in personal computing history. Looking back is not a goal on its own but a way of connecting snippets into a meaningful chain. The meaningful chain allows for the right conclusions && for the right actions. So on we go:

As you can easily derive from the history of personal computing Steve Wozniak designed the Apple II as an open personal affordable not networkable computer and published the Apple II Reference Manual that contained specs of the memory layout, described how to add hardware and peripherals etc.

At the time when business need and other influences started to kill the concept at Apple (1980) Don Estridge of IBM started to lead their PC Division and together with a dirty dozen of design and manufacturing engineers copied Steve's concept in most every detail, switched from MOS Technology to INTEL thereby saving the idea of open affordable personal computing, surely something IBM had not envisioned. GOOD can come from the BAD! After his death in '85 IBM went back to their old ways, started PS/2 - OS/2.

In the same way Apple went on to develop the LISA and the MAC, closed down on information and tried to bind SW closely to propietary HW, a concept all Manufacturers except maybe MITS with their DIY product Altair had followed before Woz.

Both of these counterreformations never found any remedy against the somehow more open concept of the so-called "industry standard PC architecture". So gradually but slowly the leadership in the development of micro and other computers drifted over to the two most decided and competent supporters and beneficiary of that architecture, Intel and Microsoft.

In the meantime a group of people at office copier machine dominator XEROX's PaloAltoResearchCenter started to really build a machine in SW the instructions of which didn't look like

LDA CC1A
ADD #00FE
STA CC1C

anymore. They called those constructs a virtual machine. These virtual machines could and should be implemented on different kinds of hardware but in reality they executed on personal computers like the Alto, the Dolphin and the Dorado. Nobody could afford those fancy machines, practically everybody in IT used a TTY then. The Sun-1 workstation appeared in 1982, 5 years after the Apple II and 1 year after the IBM PC. Even a workstation like the sun could barely run and not really run a Smalltalk Virtual Machine. It took many years to have the kind of virtual machine an Alto could drive run on a personally affordable computer.

The PARC people were not the only ones to think about and develop with virtual machines. One's gotta mention the UCSD P-System that you could install on the original PC with the benefit of having Pascal instead of Basic. Behind that compiler was an OS come virtual machine. And what's also gotta be added, is, that from at least the point on when the Bell labs people rewrote Unix in C, the Unix kernel has become a virtual machine, the model of which in the meantime has grown to be the most pervasive of all VMs.

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