[Coco] CoCoPi - getting NitrOS-9 EOU to recognize RTC?

tim lindner tlindner at macmess.org
Tue May 21 16:26:23 EDT 2019

On Tue, May 21, 2019 at 12:04 PM Allen Huffman <alsplace at pobox.com> wrote:

> What am I missing?

Nothing. Sometime things break in MAME. It's almost like I need to
make a test suite of things I am interested in. But let's dig into
this specific issue.
Starting at line 339. We see there is a msm6242 at address $FF50
(marked Cloud-9). And a ds1315 at $FF78, $FF79, an $FF7C (marked

Now we go to the NitrOS-9 Source.
On line 465 we see the Clock2.cloud9 file is created by assembling
clock2_ds1315.asm with the CLOUD9 flag.

If CLOUD9 is defined we see the clock hardware base address is FF7C,
with -4 for the ZERO, -3 for the ONE, and 0 offset for READ.
So it seems like Cloud-9 clock driver should work with the Disto MAME setting.
I remember adding these two clock chips to MAME (a long time ago) and
I remember the names matching up with existing software. But is seems
over time things changed.


On line 22 we see base address of clock is at $FF50.

tim lindner

"Proper User Policy apparently means Simon Says."

More information about the Coco mailing list