[Coco] RS232 Schematics, was DriveWire survey

[CoCoList for Color Computer Enthusiasts]

On 5/12/2014 2:00 AM, CoCoList for Color Computer Enthusiasts wrote:
>
> If we're talking about the data going in/out, right now we have variants of
> Disk BASIC and OS9 drivers that use the Becker interface in place of the
> bitbanger for DriveWire.  The FPGA connects the outside of the Becker
> inteface to a serial line and the emulators use a TCP socket, both then
> connect to a DriveWire server.  Its just faster drivewire.
Ah, got it.
>
> You could expose the USB, make the SD card slot a
> dedicated drive, allow the coco to directly access the networking on the
> pi, use the HDMI out as a terminal display, all kinds of awesome stuff!  I
> would be quite motivated to help create software to enable all of that.
> Some of what we've learned in DriveWire would help, we are pretty good at
> multiplexing dozens of data streams over one pipe.  But really its a much
> broader opportunity and deserves a better platform than DW would provide.
I agree, lots of opportunities, but I want to remain realistic. Right 
now, I'd like to get something connected to the Coco Expansion port and 
make sure I can read and write bytes to it.  Once that is in place, I'll 
move to the next step.  Right now, Pi has issues, as it is master SPI 
mode only (meaning it must be allowed to start the transfer, not receive 
it).  That throws a wrench into some of the plans, but no worries at 
present.

A 6551 interface holds a lot of value, IMHO, though, as almost all of 
the 6XXX environments used it for UART duties.  Making this working and 
putting it on a 28 pin header would mean people could pop out their 6551 
ACIA of their RS232 Pak, pop this in, and try things out with limited help.

Jim