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Re: Adt(pro)
In article
<bc6ac1d2-ca03-49ea-bb09-02fe018c2bdb@b38g2000prf.googlegroups.com>,
David Wilson <mcs6502@gmail.com> wrote:
> On Sep 19, 6:39�am, "John B. Matthews" <nos...@nospam.invalid> wrote:
>
> > > > >> Translation:
> > > > >> LDA #$10
> > > > >> STA $C08B ;ACIA_Control Register
> > > > >> LDA #$0B
> > > > >> STA $C0AA ;ACIA_Command Register
> > > > >> LDA $C0A8 ;ACIA_Data
> > > > >> RTS
>
> > Ah, I see. Then there's some kind of 32x external clock?
> > $0B (%00001011): 1 stop bit, 8 data bits, external clock, 3600 baud.
>
> The $10 stored in the control reg selects 1 stop, 8 bits, ext rx clk,
> XTL/16 bps where XTL = 1.8432 MHz so the baud rate is 115200 bps.
Thanks, David. I had the command and control registers reversed when I
tried to interpret the values.
Also, my table was wrong. I had incorrectly indicated that clearing the
low nibble of the control register specified an external clock, which is
actually specified in bit four. I think I fixed it:
<http://home.woh.rr.com/jbmatthews/ssc.html#tbl3>
> The $0B is stored in the command reg and selects no parity, no echo,
> RTS & DTR asserted, no IRQs.
I see this, now.
--
John B. Matthews
trashgod at gmail dot com
home dot woh dot rr dot com slash jbmatthews