Hi Roman, Unfortunately I'm not checking a pulse train - just a single pulse which is coming from a device triggered also by the PIC. I will be able to trigger several times in order to get an average. Also it is the length of time the pulse is high that is of interest. If it were a pulse train I would definitely do as you suggested. Slan John *************************************************************** John.Walshe@inpactmicro.com INPACT MICROELECTRONICS (Irl) Ltd 21A Pouladuff Road, Cork, Ireland, Tel: +353 21 4318296 Fax: +353 21 4318980 WWW.INPACTMICRO.COM *************************************************************** -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics