[Coco] CocoMIDI and Other Boards Available

Jayeson Lee-Steere cocolistemail at titaniumstudios.com
Fri Aug 19 01:51:44 EDT 2016

Joe Schutts pointed out that it is not uncommon for modern devices to omit
the old-school MIDI connectors. This board is definitely old-school MIDI

It would be cool to also have a card that can also be a USB MIDI host, but
I'm not aware of an easy way to implement a USB host. Some microcontrollers
support it, but things get messy with the needed software stack. To my
knowledge there is no simple Arduino implementation to borrow for example.

If you wanted to drive a USB MIDI-only device with this, my recommendation
would be to get a USB to 5 pin DIN MIDI adapter (they are crazy cheap),
then use a PC as an intermediate device.

- Jayeson

On Thu, Aug 18, 2016 at 5:26 PM, Jayeson Lee-Steere <
cocolistemail at titaniumstudios.com> wrote:

> For those not on Facebook:
> CocoMIDI 2016 boards are finally available! These follow the de facto Coco
> MIDI standard used by the original Rulaford, Glenside, etc. MIDI
> cartridges. They ended up being more expensive to build than my initial
> estimates. There are a few options available.
> John Strong is designing a case - current work-in-progress is looking
> great. Please purchase case(s) directly from him when available.
> I also have the pictured Coco 1 E-Board Solderless 64k Circuit boards.
> These allow the Coco 1 E board machines to address the full 64k. Previously
> this involved soldering an (IMO) ugly mess wires. You still need to supply
> 8 4164 DRAM chips. The color of the attached jumper wire varies - if you
> have a prefer please request a color and I will try to accommodate.
> I may be able to ship the Coco 2 SRAM boards right now, subject to testing
> this updated board design. These 64k boards are for later Coco 2 models
> which have the two white header sockets for a RAM board. The board does not
> require any soldering but a single wire jumper does need to be soldered
> onto the Coco main board. A pre-shaped wire jumper and a short length of
> solder included. You'll need tweezers/fine tipped pliers, a soldering iron
> and a helping hand to solder the jumper.
> Pricing follows. All prices are in US$. If you are in Australia, I will
> convert to AU$ and add GST. Some options are very limited quantities -
> Michael Brant​, Randy Weaver​, Ed Orbea​, Anthony Mori​ and André Ballista​
> are first in line. Please message me for a total - I check for message
> requests often. Payment will be via Paypal.
> Fully assembled and tested CocoMIDI 2016 rev 1.1 board with standard 6850
> UART.  (Boards on left of first photo). Ignore the unpopulated chip sockets
> on some of the boards in the photos - all board options come complete and
> tested. As mentioned above, no case is supplied. $79
> Fully assembled and tested CocoMIDI 2016 rev 1.0 board with standard 6850
> UART. (Board on bottom right of first photo, and in second photo). This
> earlier board revision has a number of patches on the bottom side. The wire
> patches are soldered into the board through-holes, so are very solid. These
> are functionally identical to the rev 1.1 boards, other than the lack of a
> front set of mounting holes. I'm not sure John Strong's case will even use
> these holes. $74.
> Upgrade UART to 68B50. The 68B50 are rated for 2MHz operation so Coco 3
> users may wish to choose this option. I am uncertain if any Coco MIDI
> software accesses the MIDI port with the Coco running at 2MHz - there is no
> need in assembly language and the earlier MIDI devices do not specify a
> 2MHz part. If you plan on writing a BASIC MIDI program on your Coco 2, then
> this option will allow you to use the high speed poke with confidence. Add
> $9. Fourteen only, then they are gone.
> Upgrade UART to new-old-stock, ceramic/gold, Soviet 6850 clone. Add $19.
> Two only, then they are gone. I quite like these, so grab them quick before
> I change my mind about selling them.
> Buy two or more CocoMIDI 2016 boards at once. Save $10 per board.
> E-board 64k Circuit board. $15
> 64k SRAM board for late model Coco 2: $18
> Postage is from Australia. As an example, postage and packaging to the USA
> starts at $13.50 and typically delivers within 2 weeks.
> Please note that the boards are hand-assembled in small quantities and may
> have minor cosmetic flaws. If you are unsatisfied for any reason, send back
>  boards within 15 days of receipt for a full refund (less shipping).
> Cheers,
> Jayeson
> https://drive.google.com/file/d/0B_lZwDmP8D1aZjJEczNCQ2JmbkU/
> view?usp=sharing
> https://drive.google.com/file/d/0B_lZwDmP8D1aMmxDdmNZYUJFS2M/
> view?usp=sharing

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