🚀 go-pugleaf

>>I can't vouch for the red carpet/blue carpet story, but
>>the first IBM PCs did use Intel 8086s.  They also had
>>cassette ports in the back, as some of you may recall.
>>The machine is called a PC-1 internally by IBM hardware
>>reps.  The motherboard came with 256K of RAM if I remember
>>right, and could hold 512k.  The PC-2 came out later,
>>and had an Intel 8088.  There was room on the motherboard
>>for 640k and the cassette port had dissappeared - but
>>Basic still supports it...

*AHEM*  Not quite right.  This is from someone who actually used
an original IBM PC with DOS 1.0 for a while, and now works at
IBM.  (Although comments in this message are NOT to be taken as
official statements from IBM, this is just little old me
represtenting no one but myself...)

The original IBM PC (sometimes dubbed PC-1) did indeed use an
Intel 8088, NOT the Intel 8086.  The reason for it was that
there were a great many cheap 8-bit components on the market,
and not a very many 16-bit ones.  IBM picked the Intel 8088
because internally it was 16-bit, so it would be more
attractive than a Z80, but externally it would be 8-bit,
allowing existing designs of hardware expansion to be easily
modified to work in the IBM PC.

The original operating system was supposed to be CP/M-86 from
Digitial, but due to a few events I won't go into, it ended
up being IBM PC-DOS 1.0, which they licensed from Microsoft who
bought it from someone else as DOS86.  IBM did market CP/M-86
along with IBM PC-DOS, and even a few other OSs.  (Anyone
remember the UCSD system for UCSD Pascal?  Whew!)

The IBM PC did indeed have a cassette port.  It was located
right next to the keyboard port, and was the same DIN
connector.  The only other IBM that had one was the PCjr,
although it used a different connector.

The first IBM PC had 16K of RAM soldered to the motherboard,
with empty sockets to allow up to 64K of RAM.  Expansion
through the 8-bit slots allowed expansion to 544K of RAM.
(Later BIOS upgrades which were once available through IBM
supported 640K of RAM, hard disks, and EGA.  The first IBM
PC could use NONE of these if the original BIOS is still
intact.)  The next PC after it had 64K soldered to the
motherboard and allowed 256K of expansion.

The first PC to use the Intel 8086 that I'm aware of was a
Compaq.  On this fact however, I'm not so sure.  I still have
the PC World when it was introduced, and it seemed to refer
to it as the first 8086 machine, and it explained what an
8086 was since it was new to everyone even though it's an
older chip, but I wouldn't be surprised if someone digs up
an older compatible design that used the 8086.

IBM's first PC that used an 8086 was the IBM PS/2 Model 30.
It ran it at 8MHz.  The IBM PC, PC-XT, and PCjr all used an
Intel 8088 running at 4.77Mhz.  If anyone tells you other-
wise, they are just plain wrong.  If you find someone who
claims it had an 8086, open 'er up and check.  If it has
the original IBM motherboard, it's an 8088.

- Darius
=========================================================================
   BITNET: U39648@UICVM             | "I'd rather laugh with the sinners
 Internet: u39648@uicvm.uic.edu     |         than cry with the saints,
====================================|  the sinners are much more fun,
  "Don't set fire to strangers."    |  and only the good die young."
  - Mr. Zarniwoop                   |  - Billy Joel