[Coco] MC10 guys feeling left out of the DIY discussion?

[Darren A]

On Sat, Jul 18, 2015 at 4:32 PM, S Klammer wrote:

> Yet Another Masterpiece!
>
> What other capabilities have you incorporated into your MC-11?  Enhanced
> sound?  Enchanced usage of the 6847 for more graphics capabilities over the
> MC-10?  It looks to be a drop in replacement into a MC-10...
>
> It looks like my MCX128 has been made redundant :)
>
>

The MCX128 is still a great option when using an MC-10.

The MC-11 is smaller than an MC-10 (4.3 by 3.9 inches). The prototype board
was designed to fit in a Serpac A31 case <http://www.serpac.com/a31.aspx>.
I would actually prefer just a pair of acrylic plates, but don't have any
means to produce those.

No changes have been made to the sound capabilities.
Improvements to video include:

1. Composite output instead of RF.

2. Incorporates the colorburst circuit found in the CoCo 2 to produce the
desired NTSC artifact colors.

3. Allows full use of the CG6 and RG6 graphics modes (no more wrap around).

4. The Semigraphics-6 mode can now use all 4 colors of each color set
(something a CoCo cannot do). The old behaviour of producing the vertical
stripe characters has been preserved as a legacy mode.

5. You can change the base address of video RAM to any of the four 8K
boundaries in the 32K SRAM.

6. The FS* signal from the VDG has been connected to the CPU to provide a
Vertical Sync interrupt.

7. The HS* signal from the VDG has been connected to the Pulse Accumulator
Input of the CPU. This makes horizontal sync interrupts possible and
provides an 8-bit hardware register which can act as a scan-line counter.


- Darren