[Coco] Orchestra 90/cc to Stereo Composer Conversion http://6809assemblylanguage.fortunecity.com/ORCH90CC-2-STEREOCOMPOSER.

[coco at yourdvd.net]

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!
> > 
> > 
> > 
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> 
> 
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