Personal Computers

Pre-History

 

The original computers I worked on, mostly IBM, cost hundreds of thousands or millions of dollars.  Moreover, they had special electrical and air-conditioning requirements.   The idea of my personally owning one was inconceivable.  Then DEC invented the mini-computer that could run with standard office power and cooling, but that was still tens of thousands of dollars.  This was still way out of almost anyone’s personal financial reach

 

Back in the 1970’s when I worked for Mason McDuffie, one of my co-workers thought he was going to come into possession of a discarded mini-computer.  I don’t remember the make or model, but I do know we got our hands on some of the documentation.  I actually designed a small OS for it.  But the machine never materialized so nothing came of it.

 

Later, when I was working for Breuners we were running an IBM System/370.  The computer needed more memory, which one would normally buy from IBM.  But Intel was making memory chips and competing with IBM, so we talked to them.  The Intel salesman offered me a “cosmetically flawed” Intel 8080 chip. 

 

Intel had invented the microprocessor.  Prior to that time, computer processors were multiple chips on one or more circuit boards.  The first microprocessor was the 4004, a four-bit chip.  Next came the 8008, an eight-bit chip.  The 8080 was also an eight-bit chip; I don’t know what the difference is between the 8008 and the 8080, but apparently the 8080 had enough functionality that it could actually be used to make a small computer.  (The 4004 had been designed to make calculators.)

 

Altair, a company that had previously made hobbyist rockets, put together the Intel 8080 chip, with the other necessary electronics and made the first home computer—as a kit that had to be assembled by the purchaser.

 

I was very excited at the prospect of getting my own computer.  One day I noticed there was a computer store on University Avenue in Berkeley.  A store where ordinary people could buy a computer was a completely novel concept—made possible by the invention of the microprocessor chip.  I went in to discuss with them what to do with my “cosmetically flawed”  8080 chip.  They completely deflated my hopes:  they told me that a CPU chip was worthless by itself.  I would still need memory, memory control chips, I/O control chips, a power supply, etc., etc.  In short, a CPU chip was just one component.  It was kind of like planning to buy an automobile engine and thinking I would then have a car.