pgms ok but isn't stepping right (ICD3)? [solved]

[dj41354]

I'm at a little bit of a loss here..
I'm Using a 18F4520 4Mhz external clock.
The configuration & MPLAB build seems fine, and I can program the bootload code with the ICD3.
But when I use the ICD3 to single step it's not executing correctly:
1) it does the 1st instruction (goto blstart) ok
2) the next instruction (clrf doerase) causes the execution to go to Mainloop

I must have something set up wrong on the ICD3? but I have another application I use with the same target hardware that runs and single steps fine.

Thanks in advance for any ideas on this

[Mikael Gustavsson]

I have read somewhere that the first instruction must be a NOP when debugging.
The solution would be to debug the application without the boot loader.

[dj41354]

I have read somewhere that the first instruction must be a NOP when debugging.
The solution would be to debug the application without the boot loader.

hmm..
it's the bootloader that I'm trying to debug..

When I pgm it for "release".. and run it stand alone, it doesn't connect.
Seems like I should be able to step through the bootloader code & see if it kinda looks right...

Thanks for the reply.. I'm still working on this..

[Mikael Gustavsson]

Regarding no connection you have most likely got a problem/mismatch with the oscillator and/or i/o configuration.
What does the settings file look like?