[Coco] An FPGA GIME project, and CoCo FPGA Experimenter's Board

[Mathieu Chouinard]

sound really interesting

On Mon, Oct 26, 2015 at 4:13 PM, Zippster <zippster278 at gmail.com> wrote:
> A little bit of my planning for the board...
>
> So far for features to be included on the board I have…
>
> Fully implemented bi-directional interface to the CoCo through the cartridge slot,
>                 with FPGA control of level-shifter ICs where useful
>         - 42 pins
>
> VGA output, 3 bits per channel resistor DAC
>         - 11 I/O pins
>
> RS232 I/O via Maxim 3238 serial transceiver
>         - 9 I/O pins
>
> Stereo Sound out jack - 2 channel PWM
>         - 2 I/O pins
>
> ADC input - ADC128S022CIMTX (Texas Instruments)
>         - 4 I/O pins
>
> SDRAM (32MB)
>         - 39 I/Opins
>
> 2x 16-bit shifters (32 pins) + shifter controls (8 pins)
>                 (for TTL level inputs or LVTTL outputs)
>         - 40 I/O pins
>
> ~25 pins left - (will likely end up being unshifted general I/O)
>
> A few ideas I’ve had include…
>
> Implementing a hardware sound function via PWM, that as has been suggested before,
> would allow for sampled sounds to be played on cue from the CPU without tying it up for actual
> sound generation.  Basically you'd upload your sounds to the hardware sound system when
> loading your program code and then just call a sound as needed.
>
> Implementing a WordPak style interface allowing for an 80 column or greater text output
> on a second display (VGA) for text-intensive things.  Of course there’s the possibility of
> implementing graphics modes as well.
>
> It was suggested by Camillus to use a layout for some of the I/O headers that will be compatible
> with Arduino style shields.  I think this is a good idea, and I’ll try to do that.
>
> I realize a project like this will probably only be of interest to a few people other than myself,
> but I think it may be an important one as it could lead to a few different hardware options for
> the CoCo.  At the very least it should be an excellent learning tool for interfacing FPGAs
> to an 8-bit microcomputer.   :)
>
> So I’ve put a page here I’ll post updates to for those interested…
> <https://sites.google.com/site/thezippsterzone/coco-fpga-experimenter-s-board <https://sites.google.com/site/thezippsterzone/coco-fpga-experimenter-s-board>>
>
> - Ed
>
>
>
>> On Oct 22, 2015, at 8:36 PM, Zippster <zippster278 at gmail.com> wrote:
>>
>> I think I will do the Experimenter’s board first.  It shouldn’t take too long,
>> will give me some practice with the BGA packages, and may prove to be a
>> useful tool in developing the GIME project.
>>
>> I think I have the interface to the CoCo port (level shifters) all figured out.
>> A couple of things I want to put on the board for sure will be a VGA port, and sound
>> out (resistor DACs).  So it could be configured as a video card similar to a
>> WordPak, or a sound board (among a multitude of other things).
>>
>> It looks like the interface to the cart port will use up 42 FPGA pins, so there
>> will be 130+ for other stuff!  I think you could probably make the ultimate I/O board
>> out of this thing.  :)
>>
>> - Ed
>>
>
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> https://pairlist5.pair.net/mailman/listinfo/coco



-- 
A te quaeso, sicut in Aeneidos libro quarto Aeneas, elocutus
desiderium erigendi suum obeliscum in templo Venereo Didonis, ab ea
quaesivit, tuae domi an meae?