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SWTPC 6800 Troubleshooting, cont'd

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  • Kyle Owen
    Hi folks, I think I also failed to mention in the previous discussion where I m located: Auburn, AL. Any enthusiasts in the southeast? I m currently attending
    Message 1 of 12 , Feb 18, 2012
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      Hi folks,

      I think I also failed to mention in the previous discussion where I'm
      located: Auburn, AL. Any enthusiasts in the southeast? I'm currently
      attending university here and am majoring in Electrical and Computer
      Engineering, and really enjoying it. Being in Computer Systems and
      studying assembly, and figuring out that the 68HC12 microcontroller
      uses almost all of the same instructions as the 6800 really got be
      back to the SWTPC and is my main drive currently on getting it
      working.

      I put the SWTPC 6800 on the 'scope last night and discovered that
      there is definitely data on the D0-D7 lines. The clock looks great
      too, and is right at 1 MHz, as intended. However, the data on the data
      lines appear to never change, even right after a reset. It'd help if I
      had a digitizing oscilloscope, but alas, I just have a Tek 465.

      I have the switches on the MP-A2 card set to the appropriate
      positions, according to the system checkout procedure.

      An issue I did notice was that R10 on the MP-B motherboard was
      missing. It was a 470 ohm resistor bringing the CLK2 line high. I
      don't know why it was never installed in the first place, as that
      clock line would certainly get brought rather low with enough on the
      bus, don't you think? However, despite installing the resistor, the
      computer is still not outputting any characters.

      Where can I go from here? Is there a way to bypass functionality of
      the bus, or at least test the MP-A2 independently? I am fairly
      confident that the bus is working after last night's tests, but I
      still have a bit more to test before I'll say for sure.

      It might be beneficial to replace all the chips I have duplicates of
      on the MP-A2 if all else fails. I have a fair stash of 7400-series
      chips.

      Thanks again for all the help! Maybe I'll have this working pretty soon.

      73,

      Kyle
      W4GNU
    • Evan Koblentz
      ... There s a group forming in Atlanta, and I think we have one or two members in the Carolinas and W. Virginia. But remember, this is primarily a northeast /
      Message 2 of 12 , Feb 18, 2012
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        >> Any enthusiasts in the southeast?

        There's a group forming in Atlanta, and I think we have one or two members in the Carolinas and W. Virginia. But remember, this is primarily a northeast / mid-Atlantic group.
      • Kyle Owen
        Okay, cool. I d love to talk to some of the Atlanta folks, being that I m only 2 hours away. I could definitely make it to some of those meets. NJ, on the
        Message 3 of 12 , Feb 18, 2012
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          Okay, cool. I'd love to talk to some of the Atlanta folks, being that I'm only 2 hours away. I could definitely make it to some of those meets. NJ, on the other hand, would be quite a stretch for me now.

          And I honestly can't believe it. The SWTPC is working again! Amazing how it wasn't even the computer's doings! I ended up checking out the data lines carefully after a reset and noticed that there was actual data being sent. Then I checked the RO line (RS-232 output) on the MP-S, and sure enough, it was changing quite quickly. So I hooked it up to my laptop's RS-232 port, and...nothing. Then I started poking around the end of the cable to make sure it was getting there. It was. But just to be sure it wasn't the cable, I replaced my cable with another one, and voila! It works! It sounds like the cable might have a twist or something that would make it not work. I'll check on that later.

          I put the three good 8k RAM cards in and they are definitely working as I remember. Now I'm going to play with my early 6-bit sound card and see if I can make some rudimentary music.

          Does anyone have any info on the following:
          Newtech Computer Systems Model 68 (6-bit sound card)
          JPC Products CK-7 (apparently a calendar/clock device)
          JPC Products TC-3 (apparently a high-speed cassette tape interface)

          I'd love to get the appropriate information to get these functioning. There doesn't seem to be a whole lot of info available for any of these online right now, so my chances may be slim. 

          Thanks, and 73!

          Kyle
          W4GNU

          On Sat, Feb 18, 2012 at 5:20 PM, Evan Koblentz <evan@...> wrote:
           

          >> Any enthusiasts in the southeast?

          There's a group forming in Atlanta, and I think we have one or two members in the Carolinas and W. Virginia. But remember, this is primarily a northeast / mid-Atlantic group.
        • Evan Koblentz
          ... I think it s called the Atlanta Historical Computer Society or something like that. Run by David Greelish. Google is your friend. ... Always, always,
          Message 4 of 12 , Feb 18, 2012
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            >> I'd love to talk to some of the Atlanta folks

            I think it's called the Atlanta Historical Computer Society or something like that. Run by David Greelish. Google is your friend.

            >> It sounds like the cable might have a twist or something that would make it not work.

            Always, always, always check the simple stuff BEFORE you do complicated stuff.

            >> The SWTPC is working again!

            Apparently it never wasn't.
          • Bill Sudbrink
            ... Oh! So obvious in hindsight. Gotta add that to my be sure and check list. Congrats! Bill S.
            Message 5 of 12 , Feb 18, 2012
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              Kyle Owen wrote:

              > So I hooked it up to my laptop's RS-232 port, and...nothing.
              > Then I started poking around the end of the cable to make sure
              > it was getting there. It was. But just to be sure it wasn't the
              > cable, I replaced my cable with another one, and voila! It works!
              > It sounds like the cable might have a twist or something that
              > would make it not work. I'll check on that later.

              Oh! So obvious in hindsight. Gotta add that to my "be sure and
              check" list. Congrats!

              Bill S.
            • J. Chris Hausler
              Hi Kyle, I have a couple of the Newtech 68 music boards which means I should have the docs around here somewhere. I haven t used them in some years. If you
              Message 6 of 12 , Feb 18, 2012
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                Hi Kyle,

                I have a couple of the Newtech 68 music boards which means I should have the docs around here somewhere.  I haven't used them in some years.  If you give me a couple days I can probably find the docs (but no promises until I do :-)  I have one each of the boards in my 6800 and my 6809 but quite frankly don't remember much about them.  However a favorite program I have for them (and I forget whether this was for the 6800 or 6809) was "Newtalk" by Pete Stark.  It was a talking memory dump program, great for checking the contents of memory after you had tediously entered a long program in hex as you could look at the printed listing without taking your eyes off of it and losing your place as the program would step through what was in memory and read it out to you.

                I spent a couple years working at a customer site in Atlanta back in the late 1970's (designed the automatic dispatching system software for the Atlanta Metro heavy rail transit system) and there was a very active 6800 group in Atlanta back then.

                73, Chris Hausler


                -----Original Message-----
                From: Kyle Owen
                Sent: Feb 18, 2012 6:48 PM
                To: midatlanticretro@yahoogroups.com
                Subject: Re: [midatlanticretro] SWTPC 6800 Troubleshooting, cont'd



                Okay, cool. I'd love to talk to some of the Atlanta folks, being that I'm only 2 hours away. I could definitely make it to some of those meets. NJ, on the other hand, would be quite a stretch for me now.

                And I honestly can't believe it. The SWTPC is working again! Amazing how it wasn't even the computer's doings! I ended up checking out the data lines carefully after a reset and noticed that there was actual data being sent. Then I checked the RO line (RS-232 output) on the MP-S, and sure enough, it was changing quite quickly. So I hooked it up to my laptop's RS-232 port, and...nothing. Then I started poking around the end of the cable to make sure it was getting there. It was. But just to be sure it wasn't the cable, I replaced my cable with another one, and voila! It works! It sounds like the cable might have a twist or something that would make it not work. I'll check on that later.

                I put the three good 8k RAM cards in and they are definitely working as I remember. Now I'm going to play with my early 6-bit sound card and see if I can make some rudimentary music.

                Does anyone have any info on the following:
                Newtech Computer Systems Model 68 (6-bit sound card)
                JPC Products CK-7 (apparently a calendar/clock device)
                JPC Products TC-3 (apparently a high-speed cassette tape interface)

                I'd love to get the appropriate information to get these functioning. There doesn't seem to be a whole lot of info available for any of these online right now, so my chances may be slim. 

                Thanks, and 73!

                Kyle
                W4GNU

                On Sat, Feb 18, 2012 at 5:20 PM, Evan Koblentz <evan@...> wrote:
                 

                >> Any enthusiasts in the southeast?

                There's a group forming in Atlanta, and I think we have one or two members in the Carolinas and W. Virginia. But remember, this is primarily a northeast / mid-Atlantic group.


              • Kyle Owen
                Thanks everyone! Yes, I m quite excited myself. I just got the MASM compilers going on Ubuntu, and I ve already written my first test program. Glad to see the
                Message 7 of 12 , Feb 18, 2012
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                  Thanks everyone! Yes, I'm quite excited myself. I just got the MASM
                  compilers going on Ubuntu, and I've already written my first test
                  program. Glad to see the compiler outputs in .S19 format, as I can use
                  HyperTerminal to upload those directly at a blazing 1200 baud! Sure
                  beats the regular Kansas City format through a cassette player. :)

                  Thank you, Evan, for the info. I just joined the group and look
                  forward to meeting some of the guys.

                  And thank you, Chris, for your kind offer. Take your time; I'm in no
                  hurry to get a sound card playing. I have many projects ahead of me!
                  :)

                  I am a member of the Alabama Historical Radio Society, being that I'm
                  quite interested in tube radios, especially ham "boat anchors." One of
                  the guys there mentioned that a friend of his used to buy/sell SWTPC
                  6800/9 machines for banking. He had quite the business back in the day
                  in the Birmingham area, if I recall. I think he started with the 6800
                  and moved to the 6809 with FLEX. He said he got rid of the last of the
                  machines several years ago, unfortunately. After I told him how much
                  they were going for on eBay, he was quite shocked!

                  73,

                  Kyle
                  W4GNU

                  On Sat, Feb 18, 2012 at 6:39 PM, Ray Sills <raysills3@...> wrote:
                  > Hi Kyle:
                  >
                  > Glad to hear you got the SWTPC running!  Sometimes those RS-232 cables are
                  > wired differently, depending on whether they are connecting a terminal to a
                  > modem or to a computer, etc.  Remember those DTE, DCE monikers?  Anyway,
                  > that's why the null modem was invented.... just a pair of connectors with
                  > the wiring inside crossed in the proper way to permit devices to
                  > communicate.  I bet that first cable was simply wired for some other
                  > service, like a printer or something.
                  >
                  > 73 de Ray
                  > K2ULR
                  >
                  >
                  >
                  > On Feb 18, 2012, at 6:48 PM, Kyle Owen wrote:
                  >
                  >>
                  >>
                  >> Okay, cool. I'd love to talk to some of the Atlanta folks, being that I'm
                  >> only 2 hours away. I could definitely make it to some of those meets. NJ, on
                  >> the other hand, would be quite a stretch for me now.
                  >>
                  >> And I honestly can't believe it. The SWTPC is working again! Amazing how
                  >> it wasn't even the computer's doings! I ended up checking out the data lines
                  >> carefully after a reset and noticed that there was actual data being sent.
                  >> Then I checked the RO line (RS-232 output) on the MP-S, and sure enough, it
                  >> was changing quite quickly. So I hooked it up to my laptop's RS-232 port,
                  >> and...nothing. Then I started poking around the end of the cable to make
                  >> sure it was getting there. It was. But just to be sure it wasn't the cable,
                  >> I replaced my cable with another one, and voila! It works! It sounds like
                  >> the cable might have a twist or something that would make it not work. I'll
                  >> check on that later.
                  >>
                  >> I put the three good 8k RAM cards in and they are definitely working as I
                  >> remember. Now I'm going to play with my early 6-bit sound card and see if I
                  >> can make some rudimentary music.
                  >>
                  >> Does anyone have any info on the following:
                  >> Newtech Computer Systems Model 68 (6-bit sound card)
                  >> JPC Products CK-7 (apparently a calendar/clock device)
                  >> JPC Products TC-3 (apparently a high-speed cassette tape interface)
                  >>
                  >> I'd love to get the appropriate information to get these functioning.
                  >> There doesn't seem to be a whole lot of info available for any of these
                  >> online right now, so my chances may be slim.
                  >>
                  >> Thanks, and 73!
                  >>
                  >> Kyle
                  >> W4GNU
                  >>
                  >> On Sat, Feb 18, 2012 at 5:20 PM, Evan Koblentz <evan@...> wrote:
                  >>
                  >>
                  >> >> Any enthusiasts in the southeast?
                  >>
                  >> There's a group forming in Atlanta, and I think we have one or two members
                  >> in the Carolinas and W. Virginia. But remember, this is primarily a
                  >> northeast / mid-Atlantic group.
                  >>
                  >>
                  >>
                  >
                  >
                • Dan Roganti
                  I would suggest, for the next time, to use a single-step mod. Especially for systems with no front panel, or if you don t have a logic analyzer, or emulator.
                  Message 8 of 12 , Feb 19, 2012
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                    I would suggest, for the next time, to use a single-step mod. Especially for systems with no front panel, or if you don't have a logic analyzer, or emulator. It's a very simple cheap mod. Then you can view it stepping through the code in the Monitor Rom while youre troubleshooting. Then it's easier to see when theres a stuck bit on the address, data or some other signal.Thats if you weren't getting any serial data on the serial port to your terminal.
                    Dan

                  • Al Hartman
                    I can tell you that the Newtech Sound Card was the forerunner of the Music Box on the TRS-80, and the Orch-80 is a cheap clone of both. They were designed by
                    Message 9 of 12 , Feb 19, 2012
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                      I can tell you that the Newtech Sound Card was the forerunner of the Music
                      Box on the TRS-80, and the Orch-80 is a cheap clone of both.

                      They were designed by Stewart Newfeld who later became Zebra Systems, Inc.
                      The basement of the storefront was filled with these cards.

                      Maybe is you emailed Stewart, he might have some info for you.

                      http://www.zebrasystems.com

                      I have a bunch of binders he had made to hold the docs for these boards.

                      Al Hartman

                      ________________________________________________________________________
                      Posted by: "Kyle Owen" antiquekid3@... antiquekid4

                      I put the three good 8k RAM cards in and they are definitely working as I
                      remember. Now I'm going to play with my early 6-bit sound card and see if I
                      can make some rudimentary music.

                      Does anyone have any info on the following:
                      Newtech Computer Systems Model 68 (6-bit sound card)
                      JPC Products CK-7 (apparently a calendar/clock device)
                      JPC Products TC-3 (apparently a high-speed cassette tape interface)

                      I'd love to get the appropriate information to get these functioning. There
                      doesn't seem to be a whole lot of info available for any of these online
                      right now, so my chances may be slim.

                      Thanks, and 73!

                      Kyle
                      W4GNU
                    • Kyle Owen
                      Thanks Al. I ve emailed him, so I ll see if he has any info or not. I m hoping he does, as my assembly skills are still too weak to really make use of the
                      Message 10 of 12 , Feb 19, 2012
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                        Thanks Al. I've emailed him, so I'll see if he has any info or not. I'm hoping he does, as my assembly skills are still too weak to really make use of the sound card. I've sampled me talking and a sine wave, and it is capable of reproducing rudimentary sounds. Not good enough to be understandable unless you were the one who recorded it! :)

                        Thanks again for the info!

                        Kyle
                        W4GNU

                        On Feb 19, 2012, at 16:35, Al Hartman <alhartman6@...> wrote:

                         

                        I can tell you that the Newtech Sound Card was the forerunner of the Music
                        Box on the TRS-80, and the Orch-80 is a cheap clone of both.

                        They were designed by Stewart Newfeld who later became Zebra Systems, Inc.
                        The basement of the storefront was filled with these cards.

                        Maybe is you emailed Stewart, he might have some info for you.

                        http://www.zebrasystems.com

                        I have a bunch of binders he had made to hold the docs for these boards.

                        Al Hartman

                        __________________________________________________________
                        Posted by: "Kyle Owen" antiquekid3@... antiquekid4

                        I put the three good 8k RAM cards in and they are definitely working as I
                        remember. Now I'm going to play with my early 6-bit sound card and see if I
                        can make some rudimentary music.

                        Does anyone have any info on the following:
                        Newtech Computer Systems Model 68 (6-bit sound card)
                        JPC Products CK-7 (apparently a calendar/clock device)
                        JPC Products TC-3 (apparently a high-speed cassette tape interface)

                        I'd love to get the appropriate information to get these functioning. There
                        doesn't seem to be a whole lot of info available for any of these online
                        right now, so my chances may be slim.

                        Thanks, and 73!

                        Kyle
                        W4GNU

                      • Kyle Owen
                        Well, Stewart emailed me back saying he no longer has any resources to support it anymore. Oh, well... Kyle
                        Message 11 of 12 , Feb 20, 2012
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                          Well, Stewart emailed me back saying he no longer has any resources to support it anymore. Oh, well...

                          Kyle

                          On Sun, Feb 19, 2012 at 4:35 PM, Al Hartman <alhartman6@...> wrote:
                           

                          I can tell you that the Newtech Sound Card was the forerunner of the Music
                          Box on the TRS-80, and the Orch-80 is a cheap clone of both.

                          They were designed by Stewart Newfeld who later became Zebra Systems, Inc.
                          The basement of the storefront was filled with these cards.

                          Maybe is you emailed Stewart, he might have some info for you.

                          http://www.zebrasystems.com

                          I have a bunch of binders he had made to hold the docs for these boards.

                          Al Hartman

                          __________________________________________________________
                          Posted by: "Kyle Owen" antiquekid3@... antiquekid4



                          I put the three good 8k RAM cards in and they are definitely working as I
                          remember. Now I'm going to play with my early 6-bit sound card and see if I
                          can make some rudimentary music.

                          Does anyone have any info on the following:
                          Newtech Computer Systems Model 68 (6-bit sound card)
                          JPC Products CK-7 (apparently a calendar/clock device)
                          JPC Products TC-3 (apparently a high-speed cassette tape interface)

                          I'd love to get the appropriate information to get these functioning. There
                          doesn't seem to be a whole lot of info available for any of these online
                          right now, so my chances may be slim.

                          Thanks, and 73!

                          Kyle
                          W4GNU


                        • J. Chris Hausler
                          Hi Kyle, Well I did find my Newtech Model 68 Docs and then some. What I have are the docs for the board, issues #1 and #2 of something called Newtechniques ,
                          Message 12 of 12 , Feb 21, 2012
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                            Hi Kyle,

                            Well I did find my Newtech Model 68 Docs and then some.  What I have are the docs for the board, issues #1 and #2 of something called "Newtechniques", docs on the LPF-1 Low-Pass Filter (which I never acquired) and docs on a software cassette titled "Americana Plus MC-1SW" which I may have around here somewhere but your guess is as good as mine.  There are a number of 6800 software source listings in all this.  All together it adds up to over 25 pages, mostly double sided.  If scanned to basic .pdf's, in addition to the tedium (I just finished scanning my tax returns for last year for my tax preparer and don't want to even look at the scanner right now :-) some very large files would result.  It might be easier to just run it out to the local UPS store and have hardcopies made and then mail them to you.  Anyway, when you get to a point of actually wanting to play with your unit, contact me and we'll see what can be done at that time.  Baring flood and fire it will all still be here, I don't think I've thrown out any old computer stuff I've had, and certainly no micro stuff, in 40 years.

                            73, Chris Hausler


                            -----Original Message-----
                            From: Kyle Owen
                            Sent: Feb 21, 2012 12:08 AM
                            To: midatlanticretro@yahoogroups.com
                            Subject: Re: [midatlanticretro] Re: SWTPC 6800 Troubleshooting, cont'd



                            Well, Stewart emailed me back saying he no longer has any resources to support it anymore. Oh, well...

                            Kyle

                            On Sun, Feb 19, 2012 at 4:35 PM, Al Hartman <alhartman6@...> wrote:
                             

                            I can tell you that the Newtech Sound Card was the forerunner of the Music
                            Box on the TRS-80, and the Orch-80 is a cheap clone of both.

                            They were designed by Stewart Newfeld who later became Zebra Systems, Inc.
                            The basement of the storefront was filled with these cards.

                            Maybe is you emailed Stewart, he might have some info for you.

                            http://www.zebrasystems.com

                            I have a bunch of binders he had made to hold the docs for these boards.

                            Al Hartman

                            __________________________________________________________
                            Posted by: "Kyle Owen" antiquekid3@... antiquekid4



                            I put the three good 8k RAM cards in and they are definitely working as I
                            remember. Now I'm going to play with my early 6-bit sound card and see if I
                            can make some rudimentary music.

                            Does anyone have any info on the following:
                            Newtech Computer Systems Model 68 (6-bit sound card)
                            JPC Products CK-7 (apparently a calendar/clock device)
                            JPC Products TC-3 (apparently a high-speed cassette tape interface)

                            I'd love to get the appropriate information to get these functioning. There
                            doesn't seem to be a whole lot of info available for any of these online
                            right now, so my chances may be slim.

                            Thanks, and 73!

                            Kyle
                            W4GNU




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