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Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair.

Newsgroups comp.sys.3b1
Date 2015-12-22 14:31 -0800
References <11f11849-2c2c-433a-ad2f-555403129d14@googlegroups.com> <slrnn79ivu.nhp.BPdnicholsBP@Katana.d-and-d.com> <c86d2f5f-f461-4d3f-b0ad-1e395abb58d1@googlegroups.com> <slrnn7hidn.lon.BPdnicholsBP@Katana.d-and-d.com>
Message-ID <f088a5d3-0a8f-4dcb-a364-8205bd61206a@googlegroups.com> (permalink)
Subject Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair.
From Chris Smith <protheus@byteorder.net>

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On Monday, December 21, 2015 at 9:56:15 PM UTC-6, DoN. Nichols wrote:

> 	It has a fairly large section detailing how it all works,
> including signals.  I did not look for whether that included the
> keyboard communications or not.

Now that DoN mentions this, I see a section "keyboard controller" on page 142.  It only deals with the CPU side of the interface, but it mentions "the 6850 serial keyboard controller" which should be "shown on sheet 14 of the schematics."  It isn't easy to find, but "sheet 14" is actually on page 247 of the scanned manual.  The part is labelled 13G.

There is a Motorola MC6850, which is an async serial controller, which looks a lot like what they show.  http://pdf1.alldatasheet.com/datasheet-pdf/view/4161/MOTOROLA/MC6850.html  So it's possible we're just looking at TTL serial, which is dead simple to produce with dirt cheap embedded hardware these days.  

The signals which seem to be connected externally -- based on the schematic, are:

KBRST (from the RST pin on the CPU -- probably used to reset the peripheral at boot.)
KBTXD (from the TXD line on the 6850)
KBRXD (to the RXD line on the 6850)


There's a signal called 19.2Kbd going into the send and receive clocks of the 6850, so it's probably a good guess that the peripherals operate at 19.2kbps.  Page 260 also seems to indicate that VCC is +5v.

I'm not sure how this works out at the keyboard port and a quick glance at the manual doesn't seem to show this.  I suspect the keyboard will need Vcc and ground signals on top of everything else.  So perhaps Vcc/Gnd/RX/TX/not connected -- in some order or another.  This would mean that the keyboard would need to handle the mouse as well and somehow send the data through.  This might make sense, IIRC, since the mouse generated something that looked a whole lot like key-codes.  Does anyone remember what they were?  If we're lucky, that's exactly what the keyboard needs to provide to the TTL interface.  That may be the key to building an adapter that can handle provide mouse support.

A quick look at the keyboard later may indicate where Vcc and Ground actually come in.  That would be a fine start.

Chris

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Thread

I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2015-12-18 16:43 -0800
  Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. "DoN. Nichols" <BPdnicholsBP@d-and-d.com> - 2015-12-19 03:16 +0000
    Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Peter Schmidt <peterhschmidt@gmail.com> - 2015-12-19 09:19 -0800
      Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2015-12-21 11:12 -0800
        Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. "DoN. Nichols" <BPdnicholsBP@d-and-d.com> - 2015-12-22 04:08 +0000
          Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2015-12-22 11:45 -0800
    Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2015-12-21 10:45 -0800
      Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. "DoN. Nichols" <BPdnicholsBP@d-and-d.com> - 2015-12-22 03:57 +0000
        Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2015-12-22 11:35 -0800
          Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. "DoN. Nichols" <BPdnicholsBP@d-and-d.com> - 2015-12-23 03:16 +0000
        Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2015-12-22 14:31 -0800
          Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. "DoN. Nichols" <BPdnicholsBP@d-and-d.com> - 2015-12-23 03:41 +0000
            Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2015-12-22 21:05 -0800
              Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2015-12-23 11:49 -0800
                Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2015-12-23 14:25 -0800
                Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2015-12-23 16:19 -0800
              Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. "DoN. Nichols" <BPdnicholsBP@d-and-d.com> - 2015-12-26 04:32 +0000
                Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2016-01-05 10:20 -0800
  Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Convergent MightyFrame <mightyframect@gmail.com> - 2015-12-20 13:18 -0800
    Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Convergent MightyFrame <mightyframect@gmail.com> - 2015-12-20 13:31 -0800
    Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2015-12-21 11:00 -0800
      Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. "DoN. Nichols" <BPdnicholsBP@d-and-d.com> - 2015-12-22 03:22 +0000
        Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2015-12-22 11:19 -0800
          Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. "DoN. Nichols" <BPdnicholsBP@d-and-d.com> - 2015-12-23 03:12 +0000
            Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2015-12-22 21:18 -0800
            Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Peter Schmidt <peterhschmidt@gmail.com> - 2015-12-23 05:30 -0800
      Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Convergent MightyFrame <mightyframect@gmail.com> - 2015-12-23 17:31 -0800
        Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2016-01-05 10:09 -0800
          Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. "DoN. Nichols" <BPdnicholsBP@d-and-d.com> - 2016-01-06 00:41 +0000
            Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. arnold@skeeve.com (Aharon Robbins) - 2016-01-06 18:05 +0000
              Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. "DoN. Nichols" <BPdnicholsBP@d-and-d.com> - 2016-01-07 03:42 +0000
            Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2016-01-06 17:35 -0800
  Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Dave Brower <dbrower@gmail.com> - 2016-01-07 23:25 -0800
    Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2016-01-08 13:01 -0800
  Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2016-01-08 13:11 -0800
    Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2016-02-19 14:15 -0800
      Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. 300wattwarlock@gmail.com - 2016-02-19 23:53 -0800
      Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2016-02-20 00:03 -0800
      Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Bill Gunshannon <bill.gunshannon@gmail.com> - 2016-02-20 10:56 -0500
        Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2016-02-20 11:39 -0800
          Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Bill Gunshannon <bill.gunshannon@gmail.com> - 2016-02-21 10:15 -0500
      Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2016-02-23 22:14 -0800
  Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2016-03-04 18:04 -0800
    Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. "DoN. Nichols" <BPdnicholsBP@d-and-d.com> - 2016-03-05 03:16 +0000
      Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. 300wattwarlock@gmail.com - 2016-03-05 19:08 -0800
        Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. "DoN. Nichols" <BPdnicholsBP@d-and-d.com> - 2016-03-07 04:23 +0000
          Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Chris Smith <protheus@byteorder.net> - 2016-03-08 12:28 -0800
            Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. Convergent MightyFrame <mightyframect@gmail.com> - 2017-03-28 22:33 -0700
              Re: I could use a hand locating hardware bits and pieces and/or technical documentation for repair. "DoN. Nichols" <BPdnicholsBP@d-and-d.com> - 2017-03-30 04:25 +0000

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