Re: [colorforth] Hello - and where to begin?

["Ray St. Marie" <ray.stmarie@xxxxxxxxx>]

Hi Dr. Nick, :-)    Ray here.

On Fri, Mar 7, 2008 at 6:16 AM, Nick Maroudas
<alice@xxxxxxxxxxxxxxxxxxxxxxx> wrote:
>
> Having found that Howerd Oakford's CFDOS4 floppy boots
> reliably on my 3GHz 64bit PC,

Well done. This IS excellent news. Willing to bet you've got cf on the
first 64 bit machine. Again, great stickin'-to-it-iveness.

> I think I have also found
> a use
> for the CF instruction "a" (the one that Chuck commented
> as
> "never used?").

Might be a good way to store an address you are using in one task
while PAUSEing to do another.

>It can be used to return the high 32
> half of the
> 64 bit clock counter RDTSC, which is in EDX (same as the
>  CF
> address register "a").

Neat! Well found!

> Chuck's assembly code for the CF
> word
> "time" returns only the low 32 half, which is in EAX
> (same as
> CF data stack).  On a 3 GHz clock the lower half counter
>
> whizzes around 3 times per second, which upsets Howerd's
>
> code for time calibration "cal" and millisecond delay
> "ms"
> (block 28) and hence for sounds via the 16 bit timer PIT
> 2 (block 68).  I have corrected this, and am willing to
> write
> it up in sordid detail if anyone is interested.

Pick me! pick me! i'm interested! :-)  Basically I'm interested in
every way colorforth is used.

> Incidentally, I also changed the values that need to be
> written to PIT control register 43 in order to "tie"
> PIT2 to IRPort 61 and
> "untie" it.  Howerd uses 4f and 4d; I use f and d,
> because
> Intel's book ICH7 says that bit 6 (40h) ought to be 0
> when writing to IRPort 61.  If you want to use the
> interrupts, Tie
> can be reduced to 3 and Untie to 1.

I'm not sure I understand what is being said here. This is ( like many
things) over my head a tad, I'm not ashamed to say. Please, Nick, vas
es PIT2 und IRPort 61, control reg 43, and when you say tie you mean
that PIT2 feeds IRPort 61 and then to do that you need register PIT 43
to connect these devices... um yeah? I don't know what I just said.


>
> Caritas,
>
> NickM
>

I'm glad you are having this success!
Ray

-- 
Raymond St. Marie ii,

---------------------------------------------------------------------
To unsubscribe, e-mail: colorforth-unsubscribe@xxxxxxxxxxxxxxxxxx
For additional commands, e-mail: colorforth-help@xxxxxxxxxxxxxxxxxx
Main web page - http://www.colorforth.com