[sdiy] moog module designs

[James Patchell]

It is unambiguous...just not clear when you take a quick look at it.  There 
are lots of ways to specify how a JK flip flop works...I can understand why 
some people might have trouble understanding it...good documentation is 
documentation that is not only correct...but clear.

At 12:07 PM 4/23/2005 -0700, Scott Gravenhorst wrote:
>How can that be?  If J=H and K=X (where K can be H) for output Q=H and then
>J=X (where J can be H) and K=H for output Q=L, isn't that ambiguous?  That
>is, two different outputs for the same input condition.
>
>Am I confused?
>
>James Patchell <patchell at cox.net> wrote:
> >I took at look at the ST Microelectronics data sheet...and while the truth
> >table is not done in a way I would have done it...it does fully specify the
> >next state for all possible inputs...it is just not real clear when you
> >look at it.  I have used the ST 4027's and they work fine...it looks like
> >the same guy who did the truth table must have also written the GSM spec as
> >well...
> >
> >
> >At 10:54 AM 4/23/2005 -0500, you wrote:
> >>Scot and y'all,
> >>
> >> > This is clearly contrary to the spec sheet from Philips, and I'll bet
> >> > that's true of all makers, otherwise they couldn't really call it a
> >>4027,
> >> > and in fact, I don't believe they can call a flip-flop like this a
> >>true
> >> > JK.  IMHO, these are broken.  This comment attracted my attention
> >>because
> >> > I like to play with 4xxx series CMOS and 4027 is one of my favorite
> >>toys.
> >> >  Can you give the manufacturer(s) that produced junk 4027s like this ?
> >>
> >>I checked my data sheets, I haven't looked at the actual ICs yet. ST
> >>micro is the offender based on the data sheet. Their data sheet does not
> >>have the J high, K high entry in their truth table.
> >>
> >>At the time, I was building the module, I was using an ON Semiconductor
> >>data sheet that had the correct truth table. I went back and printed out
> >>the ST data sheet and noticed they had done some strange things with the
> >>truth table.
> >>
> >>I still have to verify that the parts in my stock are ST, but, I'm
> >>almost sure they are.
> >>
> >>Tim Daugard
> >>AG4GZ 30.4078N 86.6227W Alt: 3.7 M
> >>http://home.sprintmail.com/~daugard/synth.htm
> >
> >         -Jim
> >***************************************************************
> >http://www.oldcrows.net/~patchell
> >
> >***************************************************************
> >
> >
>
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>
>-- Scott Gravenhorst | LegoManiac / Lego Trains / RIS 1.5
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         -Jim
***************************************************************
http://www.oldcrows.net/~patchell

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