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Re: Adt(pro)
In article
<8b498e0b-343b-4d27-acd5-4bd86ecd56c6@c58g2000hsc.googlegroups.com>,
BLuRry <brendan.robert@gmail.com> wrote:
> On Sep 18, 12:25�am, David Schmenk <dschm...@YUCH.gmail.com> wrote:
> > John B. Matthews wrote:
> > > In article
> > > <5c7612ce-a123-48e8-b454-585404ab4...@59g2000hsb.googlegroups.com>,
> > > �BLuRry <brendan.rob...@gmail.com> wrote:
[...]
> > >> You can key this in from the monitor to kick it in to 115.2 kbaud
> > >> (115200 baud):
> >
> > >> 300: a9 10 8d 8b c0 a9 0b 8d aa c0 ad a8 c0 60
> > >> 300g
> >
> > >> Translation:
> > >> LDA #$10
> > >> STA $C08B ;ACIA_Control Register
> > >> LDA #$0B
> > >> STA $C0AA ;ACIA_Command Register
> > >> LDA $C0A8 ;ACIA_Data
> > >> RTS
> >
> > >> Note: This is an undocumented setting which somehow works.
> > >> �Don't ask. �:-D
> >
> > > Sorry, I'm //c challenged: Is this a 6551 ACIA? Here's some info
> > > I collected:
> >
> > > <http://home.woh.rr.com/jbmatthews/ssc.html#tbl1>
> >
> > > I'm surprised that the Control register isn't mapped to slot 2
> > > ($C0AB) like the other two registers in this code.
> >
> > He just typo'd. �It is $C0AB. �Usually you would access the
> > register as $C08B,Y with Y being the slot << 4. �The IIc has the
> > the two 6551's mapped in slot 1 and slot 2 so the IIc Tech Ref
> > manual uses the non-indexed addresses.
>
> Correct .. was a typo. I was disassembling that by sight and got a
> little jumbled. That should read STA $C0AB. Anyway, that bit of
> code is used by the game server to kick the //c serial port to go
> faster.
Ah, I see. Then there's some kind of 32x external clock?
$0B (%00001011): 1 stop bit, 8 data bits, external clock, 3600 baud.
--
John B. Matthews
trashgod at gmail dot com
home dot woh dot rr dot com slash jbmatthews