From f4bjh at free.fr Mon Mar 21 18:41:19 2005 From: f4bjh at free.fr (fabrice.decrop) Date: Mon, 21 Mar 2005 19:41:19 +0100 Subject: [picsig] External oscillator Message-ID: <20050321184124.AAFB21C0023B@mwinf0212.wanadoo.fr> Hi everyone, I'm trying to make run a 16F877-20 for synthesizer locking (UMA1022 philips)...but as every electronic device, it doesn't run fine the first time. PIC Clock is working on a 12,8MHz TCXO on OSC1 pin, wich level seems to be good, but not frequency. My config word is : __CONFIG _CP_OFF & _WDT_OFF & _PWRTE_ON & _HS_OSC Could you tell me if it's correct for an external oscillator ? My PIC seems to be a 20MHz (PIC 16F877-20). Can it work for a lower frequency ? Thanks in advance for your help. -#-73's de Fabrice-#- f4bjh at free.fr From neilthomas at telkomsa.net Tue Mar 22 21:11:33 2005 From: neilthomas at telkomsa.net (Neil Thomas) Date: Tue, 22 Mar 2005 23:11:33 +0200 Subject: [picsig] External oscillator In-Reply-To: <20050321184124.AAFB21C0023B@mwinf0212.wanadoo.fr> References: <20050321184124.AAFB21C0023B@mwinf0212.wanadoo.fr> Message-ID: <42408A05.6050209@telkomsa.net> The configuration bytes seem fine. Have you checked the data sheet. You may need a buffer between your osc. and osc1 pin. Yes the pic can run at a lower frequency. It can go down to DC! i.e. you van clock it by hand. Will be a bit tedious though! I am interested in your project. I am considering a similar project using the National LMX2306 Regards, Neil ZR2NT fabrice.decrop wrote: > Hi everyone, > > I'm trying to make run a 16F877-20 for synthesizer locking (UMA1022 philips)...but as every electronic device, it > doesn't run fine the first time. > > PIC Clock is working on a 12,8MHz TCXO on OSC1 pin, wich level seems to be good, but not frequency. My > config word is : > __CONFIG _CP_OFF & _WDT_OFF & _PWRTE_ON & _HS_OSC > > Could you tell me if it's correct for an external oscillator ? > > My PIC seems to be a 20MHz (PIC 16F877-20). Can it work for a lower frequency ? > > Thanks in advance for your help. > > -#-73's de Fabrice-#- > f4bjh at free.fr > > > > _______________________________________________ > picsig mailing list > picsig at lists.tapr.org > https://lists.tapr.org/cgi-bin/mailman/listinfo/picsig > > > From f4bjh at free.fr Sat Mar 26 00:16:50 2005 From: f4bjh at free.fr (fabrice.decrop) Date: Sat, 26 Mar 2005 01:16:50 +0100 Subject: [picsig] Re : External oscillatior Message-ID: <20050326001647.DDA661C003DC@mwinf0303.wanadoo.fr> Hi Neil, Thank you very much for your answer. I think that my problem is a software problem. The bug seems to be an error on PCLATH writing. Because my software is quite large, I need the entire PCL for calling a subroutine. However, one thing is quite strange. For my software developping, I use Proteus Isi profesionnal, which can emulate and simulate PIC, with LCD and so on... Simulation runs well, but Mplab simulator crash at the same place of the real device. Maybe, is it a bug in Proteus. If you wish, I can send you my source code in private. No problem at all. but now, is it still under developpement as you can see :-) Thanks for your help -#-73's de Fabrice-#- f4bjh at free.fr The configuration bytes seem fine. Have you checked the data sheet. You may need a buffer between your osc. and osc1 pin. Yes the pic can run at a lower frequency. It can go down to DC! i.e. you van clock it by hand. Will be a bit tedious though! I am interested in your project. I am considering a similar project using the National LMX2306 Regards, Neil ZR2NT fabrice.decrop wrote: > Hi everyone, > > I'm trying to make run a 16F877-20 for synthesizer locking (UMA1022 philips)...but as every electronic device, it > doesn't run fine the first time. > > PIC Clock is working on a 12,8MHz TCXO on OSC1 pin, wich level seems to be good, but not frequency. My > config word is : > __CONFIG _CP_OFF & _WDT_OFF & _PWRTE_ON & _HS_OSC > > Could you tell me if it's correct for an external oscillator ? > > My PIC seems to be a 20MHz (PIC 16F877-20). Can it work for a lower frequency ? > > Thanks in advance for your help. > > -#-73's de Fabrice-#- > f4bjh at free.fr > > > > _______________________________________________ > picsig mailing list > picsig at lists.tapr.org > https://lists.tapr.org/cgi-bin/mailman/listinfo/picsig > > > _______________________________________________ picsig mailing list picsig at lists.tapr.org https://lists.tapr.org/cgi-bin/mailman/listinfo/picsig From neilthomas at telkomsa.net Sun Mar 27 21:07:22 2005 From: neilthomas at telkomsa.net (Neil Thomas) Date: Sun, 27 Mar 2005 23:07:22 +0200 Subject: [picsig] Re : External oscillatior In-Reply-To: <20050326001647.DDA661C003DC@mwinf0303.wanadoo.fr> References: <20050326001647.DDA661C003DC@mwinf0303.wanadoo.fr> Message-ID: <4247208A.8060106@telkomsa.net> Hi Fabrice, MPLab should take care of "calls" accross the memory boundary without you having to write to PCLATH. You only need to take care of PCLATH when you are using look-up tables that may go accross the boundary. For such a case I use the following typical code. In this case I used indirect addressing to look up an ascii value before sending it via rs232. You should be able to adapt it to your case: movfw indf movwf offset incf offset,f movlw low ascii_lookup addwf offset,f movlw high ascii_lookup btfsc carry addlw .1 movwf pclath movf offset,w call ascii_lookup ; The look up table can now be accross the 8bit add. boundary Regards, Neil ZR2NT fabrice.decrop wrote: > Hi Neil, > > Thank you very much for your answer. I think that my problem is a software problem. The bug seems to be an error > on PCLATH writing. > > Because my software is quite large, I need the entire PCL for calling a subroutine. However, one thing is quite > strange. For my software developping, I use Proteus Isi profesionnal, which can emulate and simulate PIC, with > LCD and so on... > Simulation runs well, but Mplab simulator crash at the same place of the real device. Maybe, is it a bug in Proteus. > > If you wish, I can send you my source code in private. No problem at all. but now, is it still under developpement as > you can see :-) > > Thanks for your help > > -#-73's de Fabrice-#- > f4bjh at free.fr > > The configuration bytes seem fine. Have you checked the data sheet. > You > may need a buffer between your osc. and osc1 pin. > Yes the pic can run at a lower frequency. It can go down to DC! i.e. > you > van clock it by hand. Will be a bit tedious though! > > I am interested in your project. I am considering a similar project > using > the National LMX2306 > Regards, > Neil ZR2NT > > fabrice.decrop wrote: > > >>Hi everyone, >> >>I'm trying to make run a 16F877-20 for synthesizer locking (UMA1022 > > philips)...but as every electronic device, it > >>doesn't run fine the first time. >> >>PIC Clock is working on a 12,8MHz TCXO on OSC1 pin, wich level seems > > to be good, but not frequency. My > >>config word is : >> __CONFIG _CP_OFF & _WDT_OFF & _PWRTE_ON & _HS_OSC >> >>Could you tell me if it's correct for an external oscillator ? >> >>My PIC seems to be a 20MHz (PIC 16F877-20). Can it work for a lower > > frequency ? > >>Thanks in advance for your help. >> >>-#-73's de Fabrice-#- >>f4bjh at free.fr >> >> >> >>_______________________________________________ >>picsig mailing list >>picsig at lists.tapr.org >>https://lists.tapr.org/cgi-bin/mailman/listinfo/picsig >> >> >> > > > > > _______________________________________________ > picsig mailing list > picsig at lists.tapr.org > https://lists.tapr.org/cgi-bin/mailman/listinfo/picsig > > > > > > > _______________________________________________ > picsig mailing list > picsig at lists.tapr.org > https://lists.tapr.org/cgi-bin/mailman/listinfo/picsig > > > From dvanhorn at dvanhorn.org Sun Mar 27 21:11:04 2005 From: dvanhorn at dvanhorn.org (Dave VanHorn) Date: Sun, 27 Mar 2005 16:11:04 -0500 Subject: [picsig] Re : External oscillatior In-Reply-To: <4247208A.8060106@telkomsa.net> References: <20050326001647.DDA661C003DC@mwinf0303.wanadoo.fr> <4247208A.8060106@telkomsa.net> Message-ID: <6.2.1.2.2.20050327160025.030ac038@www.dvanhorn.org> In the hobby world, sometime it seems like there is only one microcontroller out there. This sort of thing is one reason that I don't use the pic. The AVR has no holes in it's SRAM, no pages, tables can be located anywhere, and so on. Vectored ints, most instructions are one xtal clock, no read-modify-write problem.. I recently did a repeater controller (basic) in a tiny-11, which sells for $0.25. Adjustable COR debounce, ASCII text to CW, ID timer, polite ID, programmable multi-note courtesy tone, adjustable timeout timer, adjustable hang timer, That's an 8 pin chip that uses it's internal 1 MHz clock, and needs a couple R's to set the tone levels, and a keying transistor to make a basic repeater controller. (or link id'er etc) The schematic looks more like a 555 project. From lmoffitt at bellsouth.net Sun Mar 27 05:10:45 2005 From: lmoffitt at bellsouth.net (lloyds mail) Date: Sun, 27 Mar 2005 00:10:45 -0500 Subject: [picsig] Re : External oscillatior References: <20050326001647.DDA661C003DC@mwinf0303.wanadoo.fr><4247208A.8060106@telkomsa.net> <6.2.1.2.2.20050327160025.030ac038@www.dvanhorn.org> Message-ID: <006a01c5328b$54e2f490$9201a8c0@PIGGY> Share it with us dave Lloyd ----- Original Message ----- From: "Dave VanHorn" To: "TAPR PIC Mailing List" ; "TAPR PIC Mailing List" Sent: Sunday, March 27, 2005 4:11 PM Subject: Re: [picsig] Re : External oscillatior In the hobby world, sometime it seems like there is only one microcontroller out there. This sort of thing is one reason that I don't use the pic. The AVR has no holes in it's SRAM, no pages, tables can be located anywhere, and so on. Vectored ints, most instructions are one xtal clock, no read-modify-write problem.. I recently did a repeater controller (basic) in a tiny-11, which sells for $0.25. Adjustable COR debounce, ASCII text to CW, ID timer, polite ID, programmable multi-note courtesy tone, adjustable timeout timer, adjustable hang timer, That's an 8 pin chip that uses it's internal 1 MHz clock, and needs a couple R's to set the tone levels, and a keying transistor to make a basic repeater controller. (or link id'er etc) The schematic looks more like a 555 project. _______________________________________________ picsig mailing list picsig at lists.tapr.org https://lists.tapr.org/cgi-bin/mailman/listinfo/picsig