[Coco] Eureka! I'm Running My Coco 3 with Drivewire 4 Server Finally! or I Found a Bug in HDBDOS v1.4 DW4 Coco 3!

[Aaron Wolfe]

On Tue, Sep 17, 2013 at 4:49 PM, Tormod Volden <lists.tormod at gmail.com> wrote:

> Yes, I can confirm that the hdbdw4* images are built with the DW4 flag
> which replaces the "normal" serial in/out code with Darren's Turbo
> serial code. That is the only change IIRC.
>

Good, this matches the "dw4" drivers then.

> I think there is a bug in HDB-DOS for "DW4": It starts out with
> sending the "switch-to-turbo" request, however this request is sent
> with the 230K serial code, so if the server is in "slow" 115K mode it
> probably won't be able to read this request...
>

IIRC, the sequence is supposed to be sent at 230k, and the server is
supposed to be at 115.
The result of this mismatch is static and detectable, and that is what
the server is looking for.

> I quickly tried the Turbo mode on my Dragon last week without success.
> Now looking at the server code [1] I understand why: The
> "switch-to-turbo" request is answered by a switch to hard-coded 230400
> baud, instead of simply doubling the current rate. So if a
> CoCo2/1/Dragon is running at 57600 and asks for turbo, the server
> switches to 230400 instead of 115200... And if you run HDBDOSDW4 and
> configure the server for the correct 115200 as of "Possibility #2"
> above it will still jump to 230400 when HDB-DOS boots and successfully
> transmits the "switch to turbo" request. Would be great if you could
> fix up this, Aaron.

Aye, its an oversight and I will correct it very soon.
-Aaron