Keil "skipping" commands

[Zach]

I am working on a nrf51822 UART bootloader using Keil 5.14 (though I had the same problem with 5.1). If I start with the pack example dfu_dual_bank_serial_s110_pca10028 with the 8.0sdk, and try to add some additional commands (such as setting some IO lines) it looks like the compiler is skipping them. When I do a debug, Keil's Code Coverage shows that they are not executable lines. See attached image...

I tried making all the files R/W (some were marked read only), that didn't seem to help. I also played with optimization levels, the problem persisted.

Suggestions?

[Eirik Midttun]

Are you running the debugger on target or are you using the simulator? Could be that the debugger is set to simulator, in which the IO registers don't do anything.

[Zach]

Thanks, but no, the debugger is not in simulator mode.

[Eirik Midttun]

Strange. The only other thing I can think of is if the compiler determines that the code has no effect and therefore does not compile it:

• dfu_start = false; No code because the location is zero initialized.
• app_reset = (NRF...); Set the variable to the determined value.
• if (app_reset) No instruction; does it mean app_reset is always true?

If you look at what nrf_gpio_ functions there might be a similar explanation.

[Håkon Alseth]

Hi,

This will happen when you have high optimization set. For debugging purposes, I always recommend using -O0 to avoid compiler magic. See this thread for more info: devzone.nordicsemi.com/.../

Cheers, Håkon

[Zach]

I hadn't gone all the way to Level 0 optimization mainly because then the example code wouldn't fit in the allocated ROM space.