Post by thread:Q: ICD questions

Now the fun begins. I've created a multifile project and am running it (currently) on the ICD demo target. My target code is for the 877 and I have an 11.0592 Mhz oscilator module installed on the ICD demo target. It's all written as relocatable code and seems to run just fine and as expected. ISRs, PAGESELs, BANKSEL, returns and all that cool stuff we've been discussing lately. I'm happy with the execution of my code. Happy as a fly in .... Now though I have a couple of questions: F8 the StepOver command doesn't seem to work on call statements. If I set a breakpoint on a call, I end up on the first line of code of the called subroutine. I can F7 Step just fine. What's up with this???? -Walt...

"Quitt, Walter" wrote: > > Now the fun begins. > > I've created a multifile project and am running it (currently) > on the ICD demo target. My target code is for the 877 and I have > an 11.0592 Mhz oscilator module installed on the ICD demo target. > It's all written as relocatable code and seems to run just fine > and as expected. ISRs, PAGESELs, BANKSEL, returns and all that > cool stuff we've been discussing lately. I'm happy with the > execution of my code. Happy as a fly in .... > > Now though I have a couple of questions: > F8 the StepOver command doesn't seem to work on call statements. > If I set a breakpoint on a call, I end up on the first line of code > of the called subroutine. I can F7 Step just fine. > What's up with this???? > > -Walt... I see the same thing. It does it to c source that way, too. Always stops after the statement where you set your breakpoint. And it is not always easy to set the breakpoint to the line before the one you want to stop on. Mplab is broken. Sort of an "off by one" bug. Ooooh, for a decent in circuit PIC debugger (with a call stack display).... -- Robert Wuest, PE Sirius Engineering Company

>Now the fun begins. Sure does :-) >I've created a multifile project and am running it (currently) >on the ICD demo target. My target code is for the 877 and I have >an 11.0592 Mhz oscilator module installed on the ICD demo target. >It's all written as relocatable code and seems to run just fine >and as expected. ISRs, PAGESELs, BANKSEL, returns and all that >cool stuff we've been discussing lately. I'm happy with the >execution of my code. Happy as a fly in .... Would You be willing to share some pointers to the one's like me that are still left in the dark ( at least greyish ). I havent actually read the portion of the relocatable code in the user manual, then again never was bitten by the PCLATH before. So what advantages are there ? ( page boundary ? ) Any disadvantages ? ( more code, messy code ?) >Now though I have a couple of questions: >F8 the StepOver command doesn't seem to work on call statements. >If I set a breakpoint on a call, I end up on the first line of code >of the called subroutine. I can F7 Step just fine. >What's up with this???? My guess it's a Mchip 'feature', But actually that first line of the called routine isn't actually executed yet right ? so in essence you are at the call statement. ( I think ) /Tony Tony KŸbek, Flintab AB ÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓ E-mail: spam_OUTtony.kubekTakeThisOuTflintab.com ÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓÓ

part 0 3786 bytes >Now the fun begins. Sure does :-) >I've created a multifile project and am running it (currently) >on the ICD demo target.  My target code is for the 877 and I have >an 11.0592 Mhz oscilator module installed on the ICD demo target. >It's all written as relocatable code and seems to run just fine >and as expected.  ISRs, PAGESELs, BANKSEL, returns and all that >cool stuff we've been discussing lately.  I'm happy with the >execution of my code.  Happy as a fly in .... Would You be willing to share some pointers to the one's like me that are still left in the dark ( at least greyish ). I havent actually read the portion of the relocatable code in the user manual, then again never was bitten by the PCLATH before. So what advantages are there ? ( page boundary ? ) Any disadvantages ? ( more code, messy code ?) >Now though I have a couple of questions: >F8 the StepOver command doesn't seem to work on call statements. >If I set a breakpoint on a call, I end up on the first line of code >of the called subroutine.  I can F7 Step just fine. >What's up with this???? My guess it's a Mchip 'feature', But actually that first line of the called routine isn't actually executed yet right ? so in essence you are at the call statement. ( I think ) </UL> It's the same problem that you get with the simulator and with many ICE's.  The PIC uses a pipeline so one instruction is being fetched while one is executed.  When you set a breakpoint, because of this pipeline, the instruction imeadiately following the breakpoint get's fetched ready for execution and forces you to jump into the subroutine (or something like that).  Easiest way around this is to put a nop before the call to the sub, and set the breakpoint on the nop. Mike </BODY> </HTML> </x-html>

<x-flowed> >F8 the StepOver command doesn't seem to work on call statements. >If I set a breakpoint on a call, I end up on the first line of code >of the called subroutine. I can F7 Step just fine. >What's up with this???? >My guess it's a Mchip 'feature', But actually that first line of the >called routine isn't actually executed yet right ? so in essence you are >at the call statement. ( I think ) You are being bitten by 'breakpoint skidding'. Most PIC ICEs skid on breakpoints, causing this confusion and making debugging more difficult. You will see the same problem if you set a breakpoint on ANY instruction that modifies the program flow. Ideally, you would like to break BEFORE executing the line you set the breakpoint on. I *THINK* our ICE is the only one that does not skid (please correct me if anyone knows of others). It is easier to live with skidding if you avoid setting breakpoints on lines that affect the PC (goto/jmp, call, retlw, movw PC...). Jerry Merrill .....jerrymKILLspam@spam@tech-tools.com http://www.tech-tools.com FAX: (972) 494-5814 VOICE:(972) 272-9392 TechTools PO Box 462101 Garland, TX 75046-2101 </x-flowed>