In Circuit Debugging stops working?

[HenrikOlsson]

Hi Ed,
OK, several things here,

First the oscillator.
When you DEFINE OSC xx you are simply informing the compiler at which speed YOU intend to run the PIC so that it (the compiler) can figure out how many cycles it takes to PAUSE 100 or generare PWM with a certain frequency etc etc. It does not SET the frequency of the PIC in any way shape or form and it does not set any CONFIG fuses/bits either. That's up to you to do - either thru the compiler or manually in the programmers software. For a 20MHz crystal or resonator you want it set to HS.

Second, DEFINE LOADER_USED 1
This tells the compiler that you've already programmed the PIC with a small program (called a bootloader) and that it (the compiler) needs to stay away from certain areas of the program memory (or it will overwrite the bootloader). The bootloader allows the PIC to reprogram itself via a serial connection (no need for a programmer except for getting the bootloader into the PIC to begin with). It's generally used with the MicroCode Loader (but there others). So, if you're not using a bootloader don't tell the compiler that you are. (I don't think it matters in this particular case though).

Third, the MicroCode Studio ICD
To use this the PIC must have its USART pins wired thru a RS232 level converter like the MAX232 and you must specifically compile the program for use with the debugger. This is done with the ICD compile button in MicroCode Studio, THEN you program the PIC with the generated .hex file and THEN you can use the "play button" etc to run the program, set breakpoint etc. There's guide available at Rentron - read it!

/Henrik.

[Ramius]

Hi All!
You guys are very correct and I do have the MAX232 and with the 16F628A ICD works fine now with a 20 Mhz resonator. What I did not know is that it is necessary to look at the .info file for a given PIC to know what the default(s) are. Turns out that with a 16F628A the default OSC setting is XT. In the beginning of the .info file are 3 config statements that you need to copy and paste into your code to change the XT to HS. Then everything will work fine! There is one PIC I can never seem to run in ICD mode and that is a 18F1320. I know this device uses different pins for TX and RX and checking the .info the default OSC setting is 20 Mhz. Any change someone has known good working code I could use just to do some further checking? Thanks, Ed

[Ramius]

Hi All! Turns out that the 18F1320 is a "unique" PIC requiring special handling. First the following lines are required for it to operate at 20 Mhz:
#CONFIG
__CONFIG _CONFIG1H, _HS_OSC_1H
__CONFIG _CONFIG2H, _WDT_ON_2H & _WDTPS_512_2H
__CONFIG _CONFIG4L, _LVP_OFF_4L
#ENDCONFIG

Next a very wonderful person Dannel Taylor sent me the attached file for the ICD to work. As part of the "trouble shooting" process I discovered that if you jumper the TX and RX out of the MAX232 that goes to the PIC in MicroCode Studioss you can open VIEW, Serial Communicator, then "connect" and type something and if your computer is talking to the MAX232 then it will echo back what you typed! If it does not then you can check that your computer comm port settings are correct and that the MAX232 is working. It's nice to have the warm and fuzzy feelings knowing at least how far things are working! Hope this helps others.

Best, Ed

[mackrackit]

Sorry to tell you but there is nothing special or unique about it.
The configs posted are typical.

But , Good job figuring it all out.