Re: 74HC4040N vs. CD4040

On 30 Mar, 22:27, Rich Grise <r...@xxxxxxxxxxx> wrote:
On Fri, 30 Mar 2007 12:01:46 -0700, Jerry wrote:
Tim: pulses at 5v which, on the clock and reset lines appear to be
'working' -- ie the reset is pulled low or else is at 5v, similarly
the clock, but the clock doesn't trip the Qs and the reset doesn't
reset 'em! (At least, not with any -- excuse the pun -- logic).

Rich: so put pullup resistors of between 4k7 and 10k across lines
going to the clock and reset? I'll try it...

Not "across lines" - from the "clock" pin to +5v, and from the "reset"
pin to +5v:

+5V
|
[10K]
| ______
clk ----+----| HC4040
|_____

like that, one per each. (the truth is, I don't even know what you mean by
"across lines" here.)



Sorry, I'm from Barcelona...

I can report success though, the project is working after using
decoupling capacitors and pullup resistors. Many thanks to all here
who helped -- invaluable!

Jerry

.

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