Re: [CAD_CAM_EDM_DRO] Troubleshooting a BTR

On Saturday 07 August 2004 04:48 pm, Harvey White wrote:

> On Sat, 7 Aug 2004 15:13:35 -0400, you wrote:
> >On Saturday 07 August 2004 02:57 pm, Alan Marconett wrote:
> >> Hi Steve, list,
> >>
> >> Might be older then 8250. How about the old AY5-1013? What was the
> >> year of the controller?
> >
> >This would make sense if there was no CPU, as an 8250, etc. has
> > registers that need to be set up while that one you mention is settable
> > by way of DIP switches, if I'm remembering right...
>
> that's correct, the 8250 needs to be programmed, the 1013 can be
> programmed by switches, that's what all the extra pins are for.
>
> IIRC, there's going to be a baudrate generator on that, say a motorola
> 14411, for example. Look for a 1.8432 Mhz crystal, or a multiple of
> that frequency, common baudrate use.

I don't remember 14411, but I do remember a Motorola part with a number
somewhere close that that did indeed use one of those frequency crystals.
Looking in my card file I do indeed find one listing "MC14411P" and showing
me that I salvaged one back in 1985. :-)