[Coco] 2 wasted cpus?

[Kip Koon]

Willi,
I never liked the idea of pulls, so I found a far eastern source called
HKInventory who have thousands of MC68B09EPs.  That is where I bought a
couple of MC68B09Ps for my project to duplicate Grant Searle's 6-Chip 6809
Computer design. The link below shows their inventory of MC68B09EP chips in
stock.  It also shows some PLCC44 versions which I did not even know
existed!

http://hskj.hkinventory.com/0703_001A/OfferSearch.asp

You are right!  The MC68B09P just needs an external crystal & two 22pf
capacitors (if I remember correctly) to operate properly.  On my first try
building the 6-chip 6809 computer, the MC68B09P came up and running!  Before
connecting it up to anything, I measured the E clock signal from the '09 and
saw a nearly perfect square-wave.  My trouble centered around getting the
serial cable wired correctly.  I did not have any problems anywhere else in
the circuit.  :)  After some work, I was talking to my first homebuilt 6809
based microcomputer from my PC!  I used a serial to USB cable and
Hyperterminal on Windows 7 that I transferred from XP.  It was really great
to see my creation function right off from the start!  Kudos go to Grant
Searle for a fantastic design.  It was easy to follow.  I programmed in a
Basic program to list the RAM contents which worked perfectly!  I even had
it outputting everything in hexadecimal!  I loved it.  My father was quite
impressed since it all was and still is on a solderless beardboard setup.  
Anyhow, if you look on the internet, you can still find sources for the old
Motorola chips!  Unless you are lucky the first time, it may take a little
research and time to find a source you like.
Kip

-----Original Message-----
From: coco-bounces at maltedmedia.com [mailto:coco-bounces at maltedmedia.com] On
Behalf Of Willi Kusche
Sent: Friday, March 08, 2013 2:04 PM
To: CoCoList for Color Computer Enthusiasts
Subject: Re: [Coco] 2 wasted cpus?

Hi!

    Below my signature is the text of a message posted to comp.sys.apple2
last year.

Willi

============================Message text:
Alex Freed                                      Jul 20 2012, 5:08 pm A few
strange thing happened: the 6809 CPUs bought from Jameco didn't work.
Naturally first I suspected my board, but an older CPU worked fine. I got
myself a Tandy Color Computer (for $20 on e-bay) to play with the 6809 and
the CPUs from Jameco didn't work in it either. OK, so the web page says the
CPUs are "pulls". Fortunately the Jameco store is just 5 minutes driving
from my house. The technician tells me the "pulling" was done by Motorola
and they were refurbished at the factory.
And apparently mislabed. The chips are operational all right but with
internal oscillator - a crystal between pins 39 and 38. Then Q and E signals
are DRIVEN by the chip. In other words what I got were 6809
*without* the "E" suffix, but labeled  MC6809EP. These can't be used for the
Mill. Need to get them elsewhere.

At the same time I still can't figure out how to write an OS9 floppy. I had
high hopes that the CAT9 program posted to the Apple6809 group will help to
figure out which way - PO or DO is right. Guess what - both are OK with this
program! Does anyone have an Apple OS9 floppy that is known good? I'll feel
better if I can test that OS9 runs.

-Alex

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