Peter, I've done extensive prior searches on Google. Google is my standard search engine, it's in my favorites and is number 1 on my links bar; I'm not someone who asks on this list before doing my own research if that was your concern? The Frequency counter you pointed to uses a prescaler which works OK but means you lose the lowest 8 bits of binary resolution = 2560 kHz steps in counting on /256 at a gate time of 0.1 secs. Spehro and Martin's suggestions to search for 'ECL' yeilded (on Google) the On-Semi device MC10E016 that counts at 700 MHz min and 900 Typical : ) This also has Q outputs that can be read after the count has happened. Thanks to all for your input. Ted Mawson ----- Original Message ----- From: "Peter Onion" To: Sent: Monday, February 18, 2002 12:41 PM Subject: Re: [PIC]: logic gate speeds > On 18-Feb-02 Ted Mawson wrote: > > The maximum clock speed I understand that a PIC can count at is 50 MHz - > > correct? > > > > I want to count at higher frequencies - up to 500 MHz and I'm looking to use > > a logic counter to divide 500 by 16 and give an input frequency into the PIC > > of 500/16 = 31.25 MHz. > > > > There's a 7400 series chip, the 74F161 that divides by 16 but the max i/p > > frequency is 100 MHz. Are there any 7400 series other than F that can go > > faster or any equivalents that y'all know of? > > > > Can anyone point me to a counter, ideally pre-settable and with accessible > > (to read) outputs, that could take a clock input for counting faster than 100 > > MHz and divide by 16? > > > Google search for "VHF Prescaler" found me at > http://www.qsl.net/om3cph/vhf_uhf.html > > which has a 1.3Ghz freq counter based on 16F84 > > Maybe you could try google next time for yourself ? > > Peter > > -- > http://www.piclist.com hint: The PICList is archived three different > ways. See http://www.piclist.com/#archives for details. > > -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.