bill at elkcomm.com
Sun Jun 4 07:28:05 CDT 2006
Applying a 120hz pulse derived from your 4800 clock to the CTS or RTS
on the PC serial port might put data into phase with your clock. (or
at least close enough.)
On 5/22/06, Carroll Waddell <carrollwaddell at sc.rr.com> wrote:
> William Elkins wrote:
> > While it is true the audio from a cassette player is not synced the
> > waveform that was recorded on the cassette was. Bit transistions
> > occured at zero crossing on the carriers. If your clock and pc uart
> > are running independantly your bit transistions will rarely occur at
> > zero crossing. At 1200 bps the available number of carrier cycles per
> > bit of data is one or two depending on which state the data line is
> > in. At 300 bps you get 4 cycles or 8 cycles and the phase relationship
> > between the clock and the data is less important.
> > Bill
> >> At this point, all I'm trying to do is make the H8-5 think something
> >> else is a cassette player.
> >> I'm trying to feed the H8-5 AUDIO INPUT with tones just like the sound
> >> coming from a cassette player.
> >> The audio from an actual cassette is not sync'd to anything. The PLL on
> >> the H8-5 creates the clock from the audio coming from the cassette
> >> player.
> >> I haven't started to try to create the WRITE half of the project yet.
> >> I'm still just trying to make the H8 think I have an actual cassette
> >> player with a tape to load in it.
> >> Carroll
> > --
> > Delivered by the SEBHC Mailing List
> Thanks. I hadn't thought of that.
> Delivered by the SEBHC Mailing List
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