[Coco] 6309 port of NitrOS-9 Level 1

[Tormod Volden]

On Thu, Jul 23, 2015 at 5:24 PM, Bill Pierce via Coco wrote:
> Kip, to use the 6309_coco2 disk with Coco1, you must replace ALL dw modules with dw modules from the 6809_coco1 disk
> You may get by with just replacing boot_dw, rbdw, dwio and scdwv. Aaron could say more... I don't remember which modues actually deal with the baud rates. Replace them all to be safe.

The only modules which contain any baud rate specific code are dwio
and boot_dw. On coco1 they are called dwio_coco1 and boot_dw_coco1.

What I am not sure about, if you copy the 6809 versions of these into
your 6309 boot disk as suggested by Bill, is if the bit-banger code
custom-made for 6809 timing will run at the correct speed when running
on the 6309 in native mode.

The easiest way to build DriveWire capable boot disks for CoCo1,
running at 38400 baud (which is the only thing making them "coco1" and
not "coco2"), until someone adds the coco1_6309 tree and the necessary
changes in level1/bootfiles/makefile, is: Hack the
level1/bootfiles/makefile at the 2 places where it says "ifeq
($(PORT),coco1)" into "ifeq ($(PORT),coco2_6309)" and then build for
PORTS=coco2_6309. The resulting images will have 38400 baud thus in
fact be coco1 6309 builds.

Tormod