Probably because it is such an original idea that the simulator writers=20 didn't think of it. ;) I have never seen it written up anywhere. I have not used it with a 16f88, but I have with a 16f886 and that part=20 of the block diagram looks the same. Try it in silicon. Kerry On 10/14/2016 1:08 PM, David C Brown wrote: > Doesn't work in the simulator. Why doesn't that surprise me? > > On 14 October 2016 at 03:48, Kerry wrote: > >> There is an XOR gate (T0CKI XOR TOSE) that triggers the >> prescaler/counter. It is designed to allow setting which edge of T0CKI >> triggers the counter, but the following circuitry has no way to >> distinguish which signal is actually changing. It works. >> >> Kerry >> >> >> >> On 10/13/2016 5:38 PM, David C Brown wrote: >>> If there are no transitions on the input how does toggling TOSE generat= e >>> pulses? >>> >>> On 14 October 2016 at 00:06, Kerry wrote: >>> >>>> I use a different trick. >>>> >>>> 1) Make sure no more pulses will occur on the input by making it an >>>> output or analog input. >>>> 2) Toggle the TOSE bit to generate pulses to the counter until it >> counts. >>>> Kerry >>>> >>>> >>>> On 10/13/2016 4:28 PM, Denny Esterline wrote: >>>>> Fuzzy memory says it was in one of the Tips 'n Tricks books. Run sign= al >>>>> though a AND gate, second gate input hooked to a digital output pin. >>>>> Connect another output pin to the counter input pin, - I think there >> was >>>> a >>>>> resistor from the gate to the counter input to avoid contention. >>>>> In use- after count time, pull the control line to the AND gate low, >> then >>>>> clock the other pin while checking the count register. If you count h= ow >>>>> many pulses it takes to see the count register change, and you know t= he >>>>> prescaler setting, a little math gets you to the value that was in th= e >>>>> prescaler register. >>>>> >>>>> >>>>> -Denny >>>>> >>>>> >>>>> >>>>> On Thu, Oct 13, 2016 at 12:37 PM, wrote: >>>>> >>>>>> Yeah, it seems to me you count clock cycles until you get an >>>> interrupt, >>>>>> then subtract that number from 255. That will give you the starting >>>>>> count of TMR0. >>>>>> >>>>>> >>>>>> Regards, >>>>>> >>>>>> Jim >>>>>> >>>>>>> -------- Original Message -------- >>>>>>> Subject: [PIC] Timer0 prescaler >>>>>>> From: David C Brown >>>>>>> Date: Thu, October 13, 2016 2:08 pm >>>>>>> To: "Microcontroller discussion list - Public." >>>>>>> >>>>>>> >>>>>>> ISTR an application showing how you could deduce the value in this >>>>>> register >>>>>>> (mid range PICS such as 'F88) but cannot find it now. Anyone help? >>>>>>> >>>>>>> -- >>>>>>> __________________________________________ >>>>>>> David C Brown >>>>>>> 43 Bings Road >>>>>>> Whaley Bridge >>>>>>> High Peak Phone: 01663 733236 >>>>>>> Derbyshire eMail: dcb.home@gmail.com >>>>>>> SK23 7ND web: www.bings-knowle.co.uk/dcb >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> *Sent from my etch-a-sketch* >>>>>>> -- >>>>>>> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive >>>>>>> View/change your membership options at >>>>>>> http://mailman.mit.edu/mailman/listinfo/piclist >>>>>> -- >>>>>> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive >>>>>> View/change your membership options at >>>>>> http://mailman.mit.edu/mailman/listinfo/piclist >>>>>> >>>> -- >>>> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive >>>> View/change your membership options at >>>> http://mailman.mit.edu/mailman/listinfo/piclist >>>> >>> >> -- >> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive >> View/change your membership options at >> http://mailman.mit.edu/mailman/listinfo/piclist >> > > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .