Re: Apple I Schematic

[mjmahon@aol.com (Michael J. Mahon)]

Bryan Parkoff asked:

>Apple I Schematic
>
>    Is it possible that I am allowed to design and build my own printed
>circuit board from scratch by duplicating from the schematic.  It is
>necessary to do because I will be able to understand how 8-bit
>microprocessor operate by manipulating the cells/currents throughout the
>electronic path.  I can measure volt, amp, resistance, etc to determine the
>current before they can be shown on/off like binary.
>    For example, Apple I had no keyboard but have all switches.  Please
>advise.

Actually, the Apple I was not controlled by switches, as most of the
computer kits of the day were.  It was designed to be controlled by
a user-supplied ASCII keyboard.  (Of course, a keyboard is an array
of switches, but not in the sense you mean.)

A Google search (www.google.com) for <"apple i" manual> turns up:

http://emulation.net/apple1/manual/apple1manx.html

which is an HTML-ized character-recognized scan of the Apple I
manual, including a (much too small) scan of the schematics.

Character-recognition problems contribute some typos, particularly
garbling the monitor ROM listing, but with diligent work, you can
piece it together.

A clean text disassembly of the ROM with comments is:

http://www.chez.com/apple1/Docs/Apple1/WozMonitor.txt

PDF versions of the manual and the first BASIC manual are at:

http://www.chez.com/apple1/Docs/Docs.htm

Another hit on the search is:

http://www.geocities.com/~compcloset/apple1.htm

which contains nice pictures of an Apple I, including the top and
bottom of the PC board.

Reviewing these documents should answer most of your
questions about the Apple I, which, as others have pointed out,
is quite different in detail from the Apple II models.

-michael

 Email:  mjmahon@aol.com
 Home page:  http://members.aol.com/MJMahon/