[Coco] UPDATE: CoCo Related Schematics.zip :-)

Tue May 8 10:22:10 EDT 2007

DOWNLOAD PAGE IS THE SAME:
http://6809assemblylanguage.fortunecity.com/CoCoCircuitry.html

First, I have updated the zip file, to correct the glaring error in the
$FFF0-$FFFF TO $BFF0-$BFFF TRANSLATOR.pdf circuit as pointed out by
jdaggett.

I have also added the following to the zip file:

PULSE CIRCUIT FOR INFRARED LED EYES.pdf
THIS IS THE CLOCK CIRCUITRY FOR THE INFRA-RED L.E.D.'S WHICH FORM
PART OF THE ROBOTS INFRARED EYE CIRCUITRY. IT PROVIDES APPROXIMATELY
A 1.5Khz SQUARE-WAVE USED TO PULSE THE L.E.D.'S. THE ''PULSE'' IS
CONNECTED TO A 15 OHM RESISTOR TO THE CATHODE OF A BANK OF 6 I.R.
L.E.D.'S. THE CIRCUIT SHOULD EASILY HANDLE FOUR BANKS OF SIX L.E.D.'S.
EVENTUALLY THIS CLOCK WILL BE DERIVED FROM THE MICROPROCESSOR CLOCK.
THIS IS ALL PRELIMINARY WORK AND DESIGNS.

THE KITCHEN SYNC.pdf
THIS, I CALL "THE KITCHEN SYNC"
IT'S A COCO 3 SYNC GENERATOR PROVIDING POSITIVE AND NEGATIVE
GOING HSYNC, VSYNC AND CSYNC (COMPOSITE SYNC) MIGHT BE USEFUL TO
SOMEONE WITH AN ODDBALL RGB-A MONITOR FROM BACK IN THE DAY.
REMEMBER - MONITOR STILL HAS TO BE ABLE TO SYNC DOWN TO 15.75Khz.

S.A.M. SWITCH DECODING PART 1.pdf
THIS IS THE FIRST PART OF THE ADDRESS DECODER FOR THE WRITE ONLY SWITCH
ADDRESSES OF THE S.A.M. MY
SB-RCC (SINGLE BOARD-ROBOTICS CONTROL COMPUTER), DOES NOT USE THE S.A.M.
OR THE VDG, BUT ALL OF
THEIR "SWITCHES" ARE IMPLEMENTED. THE FOLLOWING CIRCUIT HAS FOUR OUTPUTS
THAT GO ACTIVE LOW AS
FOLLOWS: $FFCx* FOR ADDRESSES IN THE RANGE OF $FFC0-FFCF, $FFDx* FOR
ADDRESSES $FFD0-$FFDF, $FFEx*
FOR ADDRESSES $FFE0 TO $FFEF, AND $FFFx* FOR ADDRESSES $FFF0 TO $FFFF.
THE FIRST TWO ARE USED TO
EMULATE THE S.A.M. SWITCHES IN THE AREA OF $FFC0 TO $FFDF. THE THIRD IS
CURRENTLY UNUSED, AND THE
FOURTH, YOU SHOULD RECOGNIZE FROM THE $FFF0-$FFFF TO $BFF0-$BFFF
TRANSLATOR CIRCUIT. AS WITH ALL
THINGS, CIRCUITRY EVOLVES AND SO THIS HAS EVOLVED TO RENDER THE PREVIOUS
TRANSLATOR CIRCUIT
OBSOLETE, AS THAT FUNCTION IS NOW INCORPORATED HERE.
NOTE THAT THE R/W* LINE IS NOT INCORPORATED INTO THIS
CIRCUIT. IT RESPONDS TO THE ADDRESSES ON BOTH READ
AND WRITE CYCLES. SEE PART TWO OF THE S.A.M. SWITCHES
DECODER FOR FURTHER INFORMATION.

S.A.M. SWITCH DECODING PART 2.pdf
THIS IS PART TWO OF THE S.A.M. SWITCH ADDRESS DECODING SECTION OF THE
SB-RCC. THIS PART OF THE CIRCUIT
DECODES ALL 32 OF THE WRITE ONLY SWITCHES OF THE S.A.M. CHIP. THE
SWITCHES THEMSELVES ARE SET BY WRITING
TO AN EVEN ADDRESS (SUCH AS $FFC0) AND CLEARED BY WRITING TO THE ODD
ADDRESS (I.E. $FFC1). THESE DECODES
ARE INTENDED TO CONNECT TO SIMPLE SR FLIP FLOPS, WHICH BECOME THE ACTUAL
SWITCHES. FOR EXAMPLE, $FFC0*
GOES TO THE SET INPUT OF THE FLIP FLOP, AND $FFC1* GOES TO THE RESET
INPUT, AND SO ON FOR ALL OF THE REST
OF THE DECODES. I HAVE ALLOWED FOR THE POSSIBILITY OF MAKING THIS
CIRCUIT RESPOND TO BOTH READ AND WRITE
CYCLES, THEREBY ALLOWING A DUAL SET OF SWITCHES TO OCCUPY THE SAME
ADDRESS RANGE. A WRITE OPERATES ONE
SWITCH, WHILE A READ OPERATES THE OTHER. TO MAKE IT WORK THIS WAY, THE
R/W* INPUT OF THE CIRCUIT SHOULD BE
CONNECTED TO GROUND INSTEAD OF R/W*. THE 256K AND 512K "BANKER" BOARDS
FOR THE COCO 1 AND 2 WORKED IN
THIS FASHION, SO I HAVE ALLOWED FOR THEIR EMULATION. COOL HUH?

-----------------------

FINALLY, REMEMBER - I AM RECREATING THIS ALL OFF THE TOP OF MY HEAD
FROM MEMORY - I HAVEN'T LOOKED AT MY SCHEMATICS AND WORK SINCE LAST
NOVEMBER, SINCE I DECIDED TO MOVE AND STUCK IT ALL IN STORAGE. I THINK
I'M DOING PRETTY GOOD :-)

--ROBERT (BE ON THE LOOKOUT FOR ERRORS!)

DOWNLOAD PAGE IS THE SAME:
http://6809assemblylanguage.fortunecity.com/CoCoCircuitry.html

> -------- Original Message --------
> Subject: Re: [Coco] Orchestra 90/cc to Stereo Composer Conversion
> http://6809assemblylanguage.fortunecity.com/ORCH90CC-2-STEREOCOMPOSER.
> From: coco at yourdvd.net
> Date: Mon, May 07, 2007 7:19 pm
> To: CoCoList for Color Computer Enthusiasts <coco at maltedmedia.com>
> 
> i meant to say TSC is tied low (in the coco) - being that it is active
> high :-)
> anyway, I am about to go to work. I will update the zip file in the
> morning with four or five more circuits from my SB-RCC design - mainly
> the pulse generator for the infrared eyes, and the circuits to
> duplicate the S.A.M.'s write only switches. Later - Robert
> 
> > -------- Original Message --------
> > Subject: Re: [Coco] Orchestra 90/cc to Stereo Composer Conversion
> > http://6809assemblylanguage.fortunecity.com/ORCH90CC-2-STEREOCOMPOSER.
> > From: coco at yourdvd.net
> > Date: Mon, May 07, 2007 6:00 pm
> > To: CoCoList for Color Computer Enthusiasts <coco at maltedmedia.com>
> > 
> > The TSC is used to tristate the buffer removing a14' from the address
> > bus. In the CoCo, the TSC is always tied high and isn't used. In my
> > Robotics Control Computer, I have designed it such that the Address Bus
> > is tri-stated anytime the E clock is low, which is why I have this
> > circuit going tri-state with the TSC line. I had eventually planned to
> > duplicate the 6847, giving it access to the address bus during E-low,
> > which is why I designed this circuit this way. The duplication of the
> > 6847 is quite a ways off though. Lot's of timing issues in my design.
> > In a bit I will update the zip file to include the decoding for the
> > $FFC0 to $FFDF S.A.M. switches. My original goal was to design a fully
> > functioning coco clone, but I found it easier to design the SB-RCC
> > without video and S.A.M. wasn't necessary because of static RAM usage.
> > The zip file will eventually contain all of the circuitry that I have
> > developed over the past year in hopes that some of it may be useful to
> > those attempting to clone the CoCo. I am going to attempt to go to work
> > tonight, they would have done the surgery today even though they
> > couldn't verify the insurance, but I didn't wanna get stuck with a bill
> > I couldn't afford. Anyway, I am sitting here transcribing more
> circuitry
> > into schematics to update the zip file. The mmu I devised uses register
> > file I.C.'s (I was originally going to use static RAM for the mmu, but
> > I can't remember why I changed my mind.) - robert
> > 
> > > -------- Original Message --------
> > > Subject: Re: [Coco] Orchestra 90/cc to Stereo Composer Conversion
> > > http://6809assemblylanguage.fortunecity.com/ORCH90CC-2-STEREOCOMPOSER.
> > > From: jdaggett at gate.net
> > > Date: Mon, May 07, 2007 5:24 pm
> > > To: CoCoList for Color Computer Enthusiasts <coco at maltedmedia.com>
> > > 
> > > Interesting circuit. I have one question. The TSC line on the
> > > Translator circuit, Is 
> > > that from the TSC Input to the MC6809E?  If so it shou ld do nothing
> > > as the TSC 
> > > is an inout to the MC6809E and not an output.
> > > 
> > > james
> > > 
> > > On 7 May 2007 at 16:41, coco at yourdvd.net wrote:
> > > 
> > > > $FFF0-$FFFF TO $BFF0-$BFFF TRANSLATOR.pdf
> > > > This circuit is from a project I have been working on for over a
> > year.
> > > > It is a single-board Robotics Control Computer (SB-RCC) Designed to
> > > > run OS-9 Level I and Nitros-9 Level I with minimal fuss. To that
> end,
> > > > the SB-RCC duplicates some of the weirdness of the MC6883/74LS783
> > > > S.A.M. chip. This particular circuit is designed to translate any
> > > > address in the range of $FFF0-$FFFF appearing on the CPU's address
> > bus
> > > > (or is that buss) into $BFF0-$BFFF. Note: The S.A.M. only
> translates
> > > > addresses from $FFF2-$FFFF, but since $FFF0-$FFF1 is a "reserved"
> > > > interrupt, I figured No Harm, No Foul, and besides, it made design
> > > > much simpler. Other circuits from this design include some to
> > > > duplicate the write only switches of the S.A.M. and an MMU that
> > > > functions like the one in the CoCo 3 (I want it to eventually do
> > Level
> > > > II and the MMU isn't that difficult to duplicate) - As soon as I
> find
> > > > where I placed those schematics (they're around here somewhere),
> I'll
> > > > add them to the zip file. There is also an infrared eye circuit
> and a
> > > > 40Khz sonar circuit to allow a robot to navigate. OS-9 is
> perfect for
> > > > this sort of thing!
> > > 
> > > 
> > > 
> > > --
> > > Coco mailing list
> > > Coco at maltedmedia.com
> > > http://five.pairlist.net/mailman/listinfo/coco
> > 
> > 
> > --
> > Coco mailing list
> > Coco at maltedmedia.com
> > http://five.pairlist.net/mailman/listinfo/coco
> 
> 
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