Post by thread:[PIC:] ICD2 and HS-PLL mode

I'm experimenting with an 18F1320 and want to go to 40MHz using the PLL and a 10MHz crystal. For some reason the ICD refuses to talk to the target's debug exec at 10Mhz. It will connect to the target, identify the PIC, program it, verify the programming, but then hang a "Connecting to debug executive". I tried updating to the latest MPLAB but it didn't make any difference. Everything works fine in regular HS mode at 20Mhz. I tried a 4MHz crystal with HS-PLL mode and it worked. I guess I'll have to go out tomorrow and get some not-quite-10MHz crystals and see if it's simply a speed thing. Has anyone out there gotten HS-PLL mode to work with a 10Mhz crystal? thanks, darren -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email spam_OUTlistservTakeThisOuTmitvma.mit.edu with SET PICList DIGEST in the body

I'm not familiar with the 18f1320, but a lot of the larger 18f series chips cannot do 40 MHz. I run an 18f452 with a 10 MHz resonator and the 4x PLL fine. But, I found the 18F6720 and 18F6520 would not do 40 MHz. The original datasheet said it would do 40 MHz. A later revision said it would not. So, check the datasheet and errata! Harold {Quote hidden}> I'm experimenting with an 18F1320 and want to go to 40MHz using the PLL > and a 10MHz crystal. For some reason the ICD refuses to talk to the > target's debug exec at 10Mhz. It will connect to the target, identify > the PIC, program it, verify the programming, but then hang a > "Connecting to debug executive". I tried updating to the latest MPLAB > but it didn't make any difference. Everything works fine in regular HS > mode at 20Mhz. I tried a 4MHz crystal with HS-PLL mode and it worked. > I guess I'll have to go out tomorrow and get some not-quite-10MHz > crystals and see if it's simply a speed thing. Has anyone out there > gotten HS-PLL mode to work with a 10Mhz crystal? > > thanks, > > darren > > -- > http://www.piclist.com#nomail Going offline? Don't AutoReply us! > email .....listservKILLspam@spam@mitvma.mit.edu with SET PICList DIGEST in the body > -- FCC Rules Online at http://www.hallikainen.com -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listservKILLspammitvma.mit.edu with SET PICList DIGEST in the body

Darren, As Harold mentioned, first check the errata to be sure your device is capable of running at 40MHz. If so, the next thing to do is cycle the power on the target device after changing the pll setting in the config line. As noted in the data sheets, the pll function doesnot work until you cycle the power. When this happened to me, the ICD2 reported "Connecting to debug executive" and then hung. If this is the case, what I believe happens is that the pic doesnot change modes and the oscillator does not run so the ICD2 sits there waiting for an answer that will never arrive. It is unfortunate that the ICD2 cannot provide better error reporting to make it clear what is wrong. Good luck! Tom At 09:12 PM 5/28/2004 -0700, you wrote: {Quote hidden}>I'm experimenting with an 18F1320 and want to go to 40MHz using the PLL >and a 10MHz crystal. For some reason the ICD refuses to talk to the >target's debug exec at 10Mhz. It will connect to the target, identify >the PIC, program it, verify the programming, but then hang a >"Connecting to debug executive". I tried updating to the latest MPLAB >but it didn't make any difference. Everything works fine in regular HS >mode at 20Mhz. I tried a 4MHz crystal with HS-PLL mode and it worked. >I guess I'll have to go out tomorrow and get some not-quite-10MHz >crystals and see if it's simply a speed thing. Has anyone out there >gotten HS-PLL mode to work with a 10Mhz crystal? > >thanks, > >darren > >-- >http://www.piclist.com#nomail Going offline? Don't AutoReply us! >email .....listservKILLspam.....mitvma.mit.edu with SET PICList DIGEST in the body > -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email EraseMElistservspam_OUTTakeThisOuTmitvma.mit.edu with SET PICList DIGEST in the body

darren wrote... >I'm experimenting with an 18F1320 and want to go to 40MHz using the PLL >and a 10MHz crystal. For some reason the ICD refuses to talk to the >target's debug exec at 10Mhz. It will connect to the target, identify >the PIC, program it, verify the programming, but then hang a >"Connecting to debug executive". I tried updating to the latest MPLAB >but it didn't make any difference. Everything works fine in regular HS >mode at 20Mhz. I tried a 4MHz crystal with HS-PLL mode and it worked. >I guess I'll have to go out tomorrow and get some not-quite-10MHz >crystals and see if it's simply a speed thing. Has anyone out there >gotten HS-PLL mode to work with a 10Mhz crystal? I'm winging it here without the benefit of docs, but I can think of several problems that might be rearing their ugly heads. First, if I'm not mistaken, there was a problem with early 18F1320's that prevented them from operating properly at high speeds. I don't remember the details, but I do remember at least one very long thread on the subject last year here on the PICLIST. Second, I'm not absolutely sure (I may be thinking of the old, original ICD, not the ICD2) but I think there's a limit on how high a target clock speed the ICD2 can accomodate in debug mode, somewhere around 25 MHz or so. This isn't a limitation when using the ICD2 as a programmer, only a debugger; so you could check your HSPLL functionality by programming the part with some simple pin-twiddling code, then disconnect the ICD2 and let 'er rip and see what happens. Hope this'll help a bit... Dave D. -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listservspam_OUTmitvma.mit.edu with SET PICList DIGEST in the body

Thanks for the suggestions! It looks like I made a "software guy" error in thinking I could replace a 20Mhz crystal with a 10MHz and not change the caps. The guy that did the board design had 18pf caps and it would appear that the 10MHz crystal won't work with them. On May 29, 2004, at 10:33 AM, Dave Dilatush wrote: > Second, I'm not absolutely sure (I may be thinking of the old, > original ICD, not the ICD2) but I think there's a limit on how > high a target clock speed the ICD2 can accomodate in debug mode, > somewhere around 25 MHz or so. That would suck.. I couldn't find anything in the docs to that effect but you never know. I reckon I'll find out when I get the crystal working. thanks, darren -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads