Jim,
     Yes, 200 to 1000ns will work fine. The pulse has to be at least=20
20ns for the 74390s to respond.
Thanks,
rich!

On 7/18/2014 12:05 PM, jim@jpes.com wrote:
>   If the 20ns+ pulse can be between 200ns and 1us, then it's no problem
> at all.  Just a few delay routines.
>
> Regards,
>
> Jim
>
>> -------- Original Message --------
>> Subject: Re: [Pic] Making a special timer!
>> From: "Richard R. Pope" <mechanic_2@charter.net>
>> Date: Fri, July 18, 2014 10:39 am
>> To: "Microcontroller discussion list - Public." <piclist@mit.edu>
>>
>>
>> Bob,
>>       OK. But how do I do this? I want to put out a one second high puls=
e
>> and then pull it low. Then I want to wait for 15 seconds. Next I want to
>> output a high for at least 20ns. Output the one second pulse, wait for
>> 15 seconds, output the 20+ns pulse, output the one second pulse, and
>> continue doing this forever.
>> Thanks,
>>

--=20
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