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2024-03-02: The wiki ran out of disk space, so things were not working. This has been resolved by adding another 5GB of quota ;-) Thanks to Tim Lindner for reporting the issues. 2020-05-17: If a page gives you an error about some revision not being found, just EDIT the page and the old page should appear in the editor. If it does, just SAVE that and the page should be restored. OS-9 Al (talk) 12:22, 17 May 2020 (CDT)

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**c o m p u t e r d o c at s c dot r r dot com
**c o m p u t e r d o c at s c dot r r dot com
== Miscellaneous ==
== Miscellaneous ==
*All suggestions for 6809 and 6309 microprocessor based projects are welcome.  Please keep them both positive and helpful.  *Thank you for visiting my little corner of the Wonderful World of the Coco 1, 2, 3, the 6809 and 6309 microprocessors.   
*All suggestions for 6809 and 6309 microprocessor based projects are welcome.  Please keep them both positive and helpful.   
*Thank you for visiting my little corner of the Wonderful World of the Coco 1, 2, 3, the 6809 and 6309 microprocessors.   
*Qaplah! Shalom! Keep Having Fun!
*Qaplah! Shalom! Keep Having Fun!
--[[User:Computerdoc|Computerdoc]] ([[User talk:Computerdoc|talk]]) 21:09, 6 April 2013 (CDT)The Computer Doc
--[[User:Computerdoc|Computerdoc]] ([[User talk:Computerdoc|talk]]) 21:09, 6 April 2013 (CDT)The Computer Doc

Revision as of 08:30, 8 April 2013

Template:NavComputerDoc

Introduction

  • First and foremost, I would like express my gratitude and appreciation to Allen Huffman for extending an invitation to me to host my personal web page on his Cocopedia web server.
  • I invite you to check back periodically as I document my experiments with my Coco 3 setup and my 6809/6309 microprocessor computer projects.

Let's turn the time machine back to about 2011. I had been looking for work for about three years. One day I decided in addition to that, I would go back and explore my computer roots. Now let's really turn the time machine way back to about 1982.

In the early 1980s, my first computer was a TRS-80 Color Computer 1. It had 16K of RAM on an F version motherboard that I later upgraded to 64K. I did everything I could to find out information about that little machine. The internet certainly did not exist back then. It fascinated me and held my attention for hours on end. The only printer I had at the time was an ASR-33 Teletype with paper tape reader and punch. I don't remember whether I started out with Color Basic 1.0 or Extended Basic 1.0, but either way my primary storage medium was cassette based only. Boy, that cassette machine was a challenge to work with!  :)

Later on I eventually upgraded to a Color Computer II. The keyboard layout on this machine was the same as before but it was a lot nicer and it came with 64K of RAM! Somewhere along the way I started using 5.25" floppy drives and started experimenting with OS-9 LI v01.00.00 or 01 and for the first time I felt like I could really do something special with this machine.

Spinning the clock forward a little ways sees me purchasing my first Color Computer 3. Whether the label was TRS-80 or Tandy, I don't remember. All I knew is it had 128K of RAM! Now I really had a great and mighty computer in my collection. Also, at some point in time I eventually installed a Seagate Model Number ST-225 20MB MFM hard drive running OS-9 LII v02.00.01 on a Color Computer 3 with 128K of RAM with a Winchester 8-bit hard drive controller card from Burke and Burke.

Then the IBM PC revolution began and my computer interests migrated to building an 80286 based PC and I left the Color Computers behind forever, or so I thought.

I have always wanted to build a 6809 microprocessor based computer of some sort for the express purpose of learning microprocessor interfacing with the best and my favorite microprocessor of all time. I never had the opportunity nor the resources to build a SouthWest Technical Products Company computer back in the late 1970s as I was still in school until my graduation on June 4, 1978. All through school, however, I drooled over all the computer magazines and computer programming books I could find.

After high school graduation, I went to work with a close friend of mine who used a Motorola Exorciser running an MDOS operating system. It booted up into a monitor program called ExBug. To boot MDOS, the user first entered a one letter command with some sort of parameter and off it went booting MDOS off of an 8" floppy disk drive. Those drives were huge! The system had two drives and an 8-bit MC6800 Microprocessor ran the whole thing.

Ok, now we are up to about 2011 when I make my decision to build a 6809 microprocessor based computer. I start scouring the internet looking for people who had built any type of 6809 computer or just even had written papers on the subject. Eventually I collected several notebooks full of documentation about several dinky 6809 computer systems.

Although I had been reading Motorola Data Books for decades, I had actually never built anything. It all always seemed a bit out of my reach. Well, I finally found a very simple 6809 microprocessor based computer that only used 6 chips and you could program it in Basic! Amazingly enough, it turned out it ran a copy of Extended Color Basic from Radio Shack's old Color Computer line that I had used all those years ago. All the graphics routines were removed since the only way to talk to it was to use some type of ASCII CRT terminal or terminal program running on a PC.

My Version of Grant Searle's 6-Chip 6809 Computer

  • Narrative about my experience designing and building my version of Grant Searle's 6-Chip 6809 Computer.

I decided to use Grant's 6-chip 6809 Computer as the basis for my very first 6809 microprocessor based experimental computer. It took me several weeks studying all the datasheets before I felt confident to wire up the 6-chip computer. Initially, I built my 6-chip computer exactly like Grant's, then I added another 8K of RAM using a second 32KB cache RAM chip from an old PC motherboard. When I fired it up for the first time, it passed the smoke time with flying colors, i.e. no smoke! It did not however communicate with my Hyperterminal program I was running on my laptop. I contacted my close friend and mentor and asked him several things about RS-232 communications and he told me that that was one of the hardest parts of a microprocessor circuit to get right. Well, I finally got it to work and I was basically programming in Extended Basic. In fact Grant Searle named his version of Radio Shacks Basic "6809 Extended Basic". I was ecstatic and beside myself with joy! It was Alive! I had done it! I had built my very own 6809 microprocessor based single board computer.

I didn't take me long before I wanted to add an additional function to my computer. Back to scouring the Internet I go looking for ideas. I finally decided on adding an MC6821 Peripheral Interface Adapter along with an AY-3-8910 Programmable Sound Generator. I wanted to hear my computer. one problem lead to another problem and I finally had to scrap that idea and figure out why my RS-232 port was not working any more. After investigating for awhile, I finally put it down to think. I had been peeking and poking using the Basic interpreter to try to communication with the PIA and the PSG chips, but to no avail. I put my computer down for awhile and fix some more PC desk tops and laptops for some customers for a little while. There weren't that many.

My Version of Erturk Kocalar's SiMon6809

  • Narrative about my experience designing and building my version of Erturk Kocalar's SiMon6809

I surf and surf the internet sometimes out of sheer boredom and what do I find, but Erturk Kocalar's SiMon6809 single board computer. I think on this awhile studying the monitor program that runs on it when I see that the monitor program allows the user to enter assembler code straight into memory! No hex bytes to fool with! I loved this. I read on and it even lists the memory back to the user as in an assembler listing! Well, this is just too cool. Wouldn't have all the computer engineers from the 1970s and 1980s loved to have had a monitor like this one and running on my favorite microprocessor too!

That does it! I have to build this 8-bit 6809 based computer also! Over the next few nights I finally decide on a chip layout on my solderless breadboard and press in all the chips. In one night I end up wiring almost the entire computer. After all it is only 9 chips plus a USB prototype module. My first 6809 computer had 13 chips and 32 LEDs on just about ever signal in that computer. I had added the 32 LEDs so I could see if the computer was doing anything. The 6809 microprocessor was functioning just fine. I just could not see anything in HyperTerminal.

I had to take care of another customer's laptop so I had to put down my SiMon6809 computer for a few days. During this time, I get an offer for a friend to host a person web page on his server.

It is now April 6, 2013, its 11:43 pm and I'm plugging away entering my 6809 single board computer experiments' experiences on a brand new web page! Isn't life great!

Keep checking this web page periodically to see what new and exciting things happen with the continuing saga of the 6809 single board computer.

My Coco 3 Setup

April 4, 2013

  • Fired up my new Coco 3 for the first time and gazed upon the standard Extended Color Basic copyright message. There it was in living color, my Coco 3 is alive!

April 5, 2013

  • After having burnt an eprom with the "HDB-DOS v1.4 DW4 Coco 3" rom image a few weeks back, I install it into my Disto Super Controller. Once I had closed up the super controller, I inserted the cartridge into the Coco 3's cartridge slot and powered up the Coco 3. Behold, my eyes peered on the screen to see the Disk Extended Color Basic copyright message and below it was displayed the HDB-DOS V1.4 DW4 COCO 3 message and the OK prompt appeared with the famous flashing color cycling curser. I did not get any floppy drives out of storage yet, so my test ended here.

April 6, 2013

  • The next day saw me looking through all my computer stuff in storage for 3.5" floppy drives. I found a number of them with selectable device select jumpers, so I started a stack of them. I ended up with eight 3.5" drives with changeable drive select jumpers. I took three of them into the house and commenced to connecting up two of the drives.
  • I Connected up two 3.5" floppy drives to the Disto Super Controller and formatted a 720KB floppy disk and a 1.44MB floppy disk with the Double-density/High density hole covered up to make the floppy drive think it is a 720KB floppy. Both types of floppies formatted perfectly. I wrote a very simple basic program to read all memory locations from $8000 to $FFFF and display them as characters on the screen. I then saved the program to one of my freshly formatted floppies and typed the command NEW. Now that the basic program is not in memory anymore, I read the program off the floppy and load it into the computer's RAM memory. Then I ran the program and all the bytes stored in the eprom were being displayed as text and graphic characters. It worked perfectly!

April 7, 2013

  • I booted VCC on my Windows 7 desktop tower with the special floppy drive controller driver to enable the system to create coco compatible floppies. I loaded "NitrOS-9 6309 l2 v3.2.9 coco3 80 trk" image into virtual drive 0. I entered to infamous DOS command to boot into NitrOS-9. The white screen appeared and garbage characters filled the screen. I said, "What?". It took me a while to realize my coco 3 is still using an MC68B09EP microprocessor chip. Ah ha! I needed the 6809 boot image. I had been using the 6309 version of the boot image, that I had completely forgotten that my real coco was still running the original Motorola microprocessor.

April 8, 2013

  • I inserted the NitrOS-9 boot disk into the coco 3's floppy drive, enter the DOS command and behold, NitrOS-9 started booting!  :) I love it! My favorite disk operating system is finally booting on my real coco 3! Now to test some more 3.5" floppy drives.

Biography

My professional biography will go here.

Resume of Kip Koon

  • Professional inquiries may be sent to me via email to:
    • c o m p u t e r d o c at s c dot r r dot com

Miscellaneous

  • All suggestions for 6809 and 6309 microprocessor based projects are welcome. Please keep them both positive and helpful.
  • Thank you for visiting my little corner of the Wonderful World of the Coco 1, 2, 3, the 6809 and 6309 microprocessors.
  • Qaplah! Shalom! Keep Having Fun!

--Computerdoc (talk) 21:09, 6 April 2013 (CDT)The Computer Doc