Thanks Oliver, nice to know that. :0) (
El sáb., 5 sept. 2020 10:17, 'Oliver Seitz' via jallib < [email protected]> escribió: > No real help, just a bit of smartassing... ;-) > > > On certain chips like PIC18fxxk22 or PIC18Fxxk42 (and probably some more) > the timer can run on the full Fosc speed. That is up to 64MHz. So a > resolution of around 16 nanoseconds is possible. Of course the 16 bit > timer then overflows after about one millisecond. You can reduce the > resolution by prescaling, or catch the overflows using the timer interrupt > to increase an additional counter. As JAL allows variables of up to 256 > bytes, you can capture times of about 2.5*10^607 years, even at the full > resolution. The universe exists since about 5*10^9 years, so that should > suffice all needs. > > Greets, > Kiste > > Am Samstag, 5. September 2020, 09:55:03 MESZ hat Jesito's μFabLab < > [email protected]> Folgendes geschrieben: > > > Many thanks Rob. I have to figure out how to do it. Is the timer working > at the MCU clock speed?. If so the 16 bit value might be too small to hold > the pulse length for i.e. a 5 sec pulse, isn't it?. I suppose some > prescaling should be done there... Have to investigate and read more on > that. > Kind regards. > Jes. > > > El jueves, 3 de septiembre de 2020 a las 18:51:51 UTC+2, > [email protected] escribió: > > Hi Jes, > > I just checked but I was mistaken, there is a procedure that calculates a > value for the timer based on a frequency. > > If you want to measure the length of a pulse you can use the capture mode > of a timer which is available in many PICs, for example the 16F1823.From > the datasheet: > Capture mode makes use of the 16-bit Timer1 > resource. When an event occurs on the CCP1 pin, the > 16-bit CCPR1H:CCPR1L register pair captures and > stores the 16-bit value of the TMR1H:TMR1L register > pair, respectively. An event is defined as one of the > following and is configured by the CCP1M<3:0> bits of > the CCP1CON register: > • Every falling edge > • Every rising edge > • Every 4th rising edge > • Every 16th rising edge > When a capture is made, the Interrupt Request Flag bit > CCP1IF of the PIR1 register is set. The interrupt flag > must be cleared in software. If another capture occurs > before the value in the CCPR1H, CCPR1L register pair > is read, the old captured value is overwritten by the new > captured value. > > Kind regards, > > Rob > > ------------------------------ > *Van:* [email protected] <[email protected]> namens Jes < > [email protected]> > *Verzonden:* donderdag 3 september 2020 13:45 > *Aan:* [email protected] <[email protected]> > *Onderwerp:* Re: [jallib] Some help needed to measure pulse length > > Thanks Rob, I look for it, just what I needed to know :0) > > El jue., 3 sept. 2020 12:01, Rob CJ <[email protected]> escribió: > > Hi Jes, > I thought there is already a Jal library to measure the width of a pulse > created by Matt. Would that do the job? > > Met vriendelijke groet, > Rob Jansen > ------------------------------ > *From:* [email protected] <[email protected]> on behalf of > Jesito's μFabLab <[email protected]> > *Sent:* Thursday, September 3, 2020 10:49:48 AM > *To:* jallib <[email protected]> > *Subject:* [jallib] Some help needed to measure pulse length > > Hello, > I'm new to JAL and I would like to measure the length of some pulses that > can be as long as 5 sec and as short as 1/8000 of second. > I have a handful of different pics, but ideally I would like to use a > small one, I just need one pin for the pulse, two more to interface to an > I2C small display and one more to reset and restart the measure. > Could anyone point me to an example that could guide me through this?. > I love the cleanless and simplicity of JAL. > Thanks in advance. > Jes. > > -- > You received this message because you are subscribed to the Google Groups > "jallib" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/jallib/29ca65ab-4f67-4e77-a321-9162fd396026n%40googlegroups.com > <https://groups.google.com/d/msgid/jallib/29ca65ab-4f67-4e77-a321-9162fd396026n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > -- > You received this message because you are subscribed to the Google Groups > "jallib" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/jallib/AM0PR07MB62419C76A4D0F51F787AE7F5E62C0%40AM0PR07MB6241.eurprd07.prod.outlook.com > <https://groups.google.com/d/msgid/jallib/AM0PR07MB62419C76A4D0F51F787AE7F5E62C0%40AM0PR07MB6241.eurprd07.prod.outlook.com?utm_medium=email&utm_source=footer> > . > > -- > You received this message because you are subscribed to the Google Groups > "jallib" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > > To view this discussion on the web visit > https://groups.google.com/d/msgid/jallib/CAJSrQ%3Df1Lm6tHoKCfC4LW68OcQgsKw5FUeGQgaKaiag5oKV8EA%40mail.gmail.com > <https://groups.google.com/d/msgid/jallib/CAJSrQ%3Df1Lm6tHoKCfC4LW68OcQgsKw5FUeGQgaKaiag5oKV8EA%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > > -- > You received this message because you are subscribed to the Google Groups > "jallib" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > > https://groups.google.com/d/msgid/jallib/a079e103-5ea2-463a-b57d-53ad94caa730n%40googlegroups.com > <https://groups.google.com/d/msgid/jallib/a079e103-5ea2-463a-b57d-53ad94caa730n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > -- > You received this message because you are subscribed to the Google Groups > "jallib" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/jallib/252643382.3502892.1599293709605%40mail.yahoo.com > <https://groups.google.com/d/msgid/jallib/252643382.3502892.1599293709605%40mail.yahoo.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "jallib" group. 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