Foreword
I was in the sixth grade when I got my first transistor radio.
That might have been the most important gift of my life. I found out about
music, and I knew that it was a big thing in my life, all from this small,
handheld, 10-transistor radio. I could sleep with music all night long, and did
so that entire year. My father was working on missile guidance technology for
military projects around this time and showed me how tightly transistors could
be packed. He also told me how chips were coming with more than one transistor
on them, for even more space and weight savings. I commented that they were
designing these things to make better and smaller radios, and he told me, no,
that they were being designed for military and commercial uses and that only
after a long time they'd filter down to consumer products that we used in our
lives and homes. That thought bummed me out that normal people in their homes
wanting good products were not driving technology.
My introduction to electronics was accidental. I lived in a new
community surrounded by orchards. It was Santa Clara Valley, California, but it
is now called Silicon Valley. I had lots of local childhood friends who were
interested in electronics, and we'd do gardening to be paid in parts, like
resistors. I read a book about a ham radio operator solving a kidnapping and
found that anyone of any age could be a ham. You didn’t have to be older as
with car licenses. So by sixth grade I had my ham license and was learning
electronics back in the days of tubes.
One day I stumbled across a journal in a hall closet of my
home. It had articles about early computing projects. This was around 1960,
when computers were unknown to mortals and filled entire rooms. I read articles
on strange storage devices, Boolean algebra, and logic gates, and how they
could be combined. What amazed me most was that none of this stuff was too hard
for a fifth grader to follow. You didn't need advanced math to understand
binary arithmetic or logic gates. I became fascinated by what I'd stumbled
onto. Based on what I'd read and what my father could teach me, I worked on a
couple of large science fair projects in sixth and eighth grade demonstrating
hundreds of transistors and diodes, all doing logic. One played tic-tac-toe,
which I thought was a game of logic (I now know that it's more a game of
psychology). The other project added and subtracted 10-bit numbers. I had no
idea that I was on the right path to learning how to design computers or that
there were jobs in this field. In fact, I was on a search to find out what a
computer was. I myself was too shy to ask or read to get such answers.
At another science fair I stumbled onto a project with a
stepping motor advancing a pointer to switches where you could set up
operations to be done. This motor could loop or back up, depending on results.
This was the first time in my life that I learned that computers had
instructions to do things like my adder/subtractor did, and that it could
repeat those instructions.
We had no computer at our high school, but because I was so
advanced by then in electronics, my teacher, John C. McCullum, a great teacher,
arranged for me to learn more by programming a computer at a company in Sunnyvale. In those days just the word "computer" brought looks of awe. I came to love all
that I could do in FORTRAN that year. I also stumbled upon a manual at Sylvania titled The Small Computer Handbook. It described a real minicomputer, the
PDP-8. The engineers let me have that manual, and it changed my life forever.
Now I had a manual that described a real computer and its
architecture and included instructions. I also had some chip catalogs, back
when you could get only one gate on a chip. And I had my knowledge of how to
combine gates into things like adders. So for the rest of high school, my
favorite pastime became designing minicomputers on paper. When a single chip
cost $50 (maybe that's $500 today), you don't have the parts to build your own
computer. I found how to get manuals describing various minicomputers from Digital,
HP, Varian, DEC, and so on. I designed my own versions of these machines over
and over. As chips got better, my designs took fewer and fewer parts. My goal
became to beat my prior design whenever I redesigned the same computer again. I
got very skilled at digital design this way. I had no endpoint; you can always
think of one more way to save another chip in a design.
I had no friends, parents, or teachers doing this with me, nor
was anyone even aware that I was doing it. My computer designs were weekend
projects in my room with my door shut. I sometimes would go late into the
night, and it helped to drink cokes. The Data General Nova was introduced. When
I finally got around to designing this computer, I found that it took half as
many chips as my other designs, due to a unique architecture. That changed my
life a lot, too. If you design a computer architecture based on what chips are
available, it can save a lot of parts.
All these minicomputers had front rectangular plates full of
switches and lights. They were intimidating and commercial looking and belonged
in racks on factory floors. But if they could run FORTRAN, that could even
enable a mere mortal to use them to play games and solve problems. I knew what
I needed and told my father that someday I'd have a 4K NOVA computer. When he
pointed out that it cost as much as a house, I said I'd live in an apartment,
but I'd have my own computer someday.
I could design computers but couldn't afford the parts to build
them.
After some college, I wound up designing chips for HP's early
scientific calculators. I worked on a lot of interesting side projects, but
lost track of minicomputers and overlooked the introduction and advancement of
microprocessors. In 1974 I saw my first Pong game in a bowling alley. As I
stared, mesmerized, at the screen, it occurred to me that I could build a Pong.
I could never afford an output device, but like everyone else, I had a color TV
at home. There was no video-in jack, but in those open days, you got schematics
with your TV. I knew TV signals and how they worked from high school
electronics, and I knew digital design, so it wasn't long before I built my own
Pong, using very few chips.
Later in 1974 I visited an old friend, famous phone phreak John
Draper, aka Captain Crunch. He was typing on a teletype, an input/output device
that I myself could never afford. He was playing chess with a computer in Boston. Then he showed me how he could have the teletype type out a list of computers, and
he could switch to one at Berkeley. It was the early Arpanet, and you dialed
into a number at Stanford using a modem to get onto it.
I absolutely had to do this thing that made you like a king,
doing what nobody else could do. I had just built my Pong and knew how to get
signals onto a TV screen. So I designed and built a terminal that could put
letters and numbers on my home TV. I had to buy a keyboard for $60 and that was
very expensive for me, but was barely affordable. I did indeed access the
Arpanet a few times, but wasn't so much interested in using those computers as
just in knowing that I could reach out to such distant places. It was like ham
radio, and also like phone phreaking, in that sense.
So a $60 uppercase-only keyboard and my Sears color TV gave me
the input/output I needed at an affordable cost. Steve Jobs said "let's sell
it" and we did sell a number to a local timeshare outfit called Call Computer.
Next, in 1975, the Homebrew Computer club started. I got
tricked into going. I never would have gone to something based on microprocessors
because I didn't know what a microprocessor was. I didn’t know that you could
buy an enhanced microprocessor, a CPU, in a case called the Altair. I didn't
know that you could add enough to this processor to make it a computer. I was
told that a new club was being formed for people with terminals and the like. I
figured it would be a great chance for a shy guy to show off with his own video
terminal based on very cheap chips.
I got scared the first night at the Homebrew Computer Club.
Everyone knew what was going on with these new affordable "computers" I took
home a microprocessor data sheet, and to my surprise, this chip was the CPU
that I'd grown up designing in high school. I was back in business. I saw that
night that soon I'd design or buy a 4KB computer and run FORTRAN for myself
finally.
Rather than design a computer from scratch, I saw a shortcut. I
could take my terminal with human input and output, and combine it with a
microprocessor and some RAM. I'd actually built a computer of my own design
five years earlier, one equivalent to the Altair with 256 bytes of RAM and
switches and lights on a front panel. I didn’t want to do that again. I didn't
need to wire dozens of switches and have the chips to get them to the memory of
a computer. That took too many parts and chips and money. Our calculators at HP
had ROMs, and they ran a program when you turned them on that waited for a user
to press human buttons and then the program did the right things. I saw that I
could write a short program that monitored the keyboard for input to do what
the old front panels had done. I called this program a monitor. It took 256
bytes, which was two PROM chips in 1975.
I first got working on what was to be the Apple I, using static
1K RAM chips. But it took 32 of these chips to have 4KB of RAM, enough for a
computer language. The 4K dynamic RAMs were just being introduced, the first
RAMs to be cheaper than magnetic core memories. I bought some from a fellow at
our club and got them working on my computer. I had to design some refresh
circuitry, but overall, I saved so many chips and dollars that it was the right
way to go. If you look back, you'll find that every single other hobby computer
back then used static RAMs because they involved less design work.
I passed out schematics and code listings freely at our club,
hoping that others would now be able to build their own computers. It took
another four months for me to write a BASIC program for this computer. I'd
never studied computer language writing, but figured out good approaches for
that. Steve Jobs said that there was a lot of interest in having computers but
not in wiring them up, so why don't we start a company to make PC boards for
$20 and sell them for $40. We'd have our own company and all. Steve came up
with the name Apple Computer. I sold my most valuable possession, my HP-65
calculator. We came up with a few hundred dollars and started this company.
After the PC board was done, Steve struck up a partnership with
Paul Terrell at the Byte Shop, the only computer store in our region, to sell
it fully built and assembled computer boards for $500 each. I was into
repeating digits, so we priced it at $666.66 retail.
We did not make or sell a lot of Apple I computers over the
next year, but we had other jobs. We did get our name and computer
characteristics in many articles over that year, and it was easy to see that
Apple Computer was getting very well known in some circles.
I look back on my Apple I design and actually have trouble
figuring out some of it. My designs back then were sometimes too clever to
figure out. They were designed to save parts and cost.
The Apple ][ was really the computer designed from the ground
up that would kick off personal computing on a large scale. But the Apple I
took the biggest step of all. Some very simple concepts are very hard to do the
first time. This computer told the world that small computers should never
again come with geeky front panels, but rather with human keyboards, ready to
type on. After the Apple I, Processor Technology introduced the SOL computer,
and it also came with a keyboard and monitor and became the hottest selling
Intel-based hobby computer, selling thousands a month. Contrast that with the
Apple I, of which we sold maybe only 150. The Apple ][ was to be the third
low-cost computer to come with a human keyboard.
Best regards,
Steve Wozniak
The previous text was the forward for the book "APPLE I Replica Creation: Cack to the Garage" by Syngress Publishing for use with the Introduction to digital logic article sampled from this book.
Steve, if you happen by this page.. Thank you for everything you have done for computing. You are one of my heros. =) If you are ever in Kansas City, I would love to talk with you over dinner or something.. Drop me a line.
