Code not going directly to main loop

Cooke.Ernest · ‎2017-06-22

Posted on June 22, 2017 at 11:16

Hi,

I am currently in the process of converting project code I have using the Standard peripheral library to the Hardware Abstraction Layer (HAL).

I noticed that when I try to debug the code and place a breakpoint in the main loop that the code does not go directly to the main loop when I press the 'Run' (F5) button in Keil uVision. The 'Run' button instead must be pressed 4 times before it goes to the main loop.

Before the code goes to the main loop, it is caught in the following location in the startup file.

After this I can get the code to execute a basic function i.e.

blink an

LED.

However when I try to execute the code in standalone mode it does not work.

When I tried this code using the

Standard peripheral library, it went directly to the main loop the first time I pressed the 'Run' button in debug mode and it worked fine in standalone mode i.e. I got the LED to blink.

Does anyone have any suggestions as to what the issue might be or how I could solve it?

Kind Regards,

Ernest

#main-loop #standard-peripheral #stm32f1 #debug #hardware-abstraction #standalone-mode #startup-code

Cooke.Ernest · ‎2017-07-05

Posted on July 05, 2017 at 12:32

I looked through the code but I could not find

rdimon-crt0.o or rdimon in the startup file?

tomtom9195 · ‎2017-07-05

Posted on July 05, 2017 at 17:46

rdimon-crt0 is part of the GCC tool chain but I see you are using Keil which will provide its own startup code.

I think this addresses your problem:

http://www.keil.com/support/docs/3614.htm

By default the tool chain is likely to use semihosting. As explained in the above link you need to either:

Provide retarget.c which redirects the semihosting library calls (from printf etc.), see:

http://www.keil.com/support/man/docs/gsac/gsac_retargetcortex.htm

or use the Keil Compiler pack

or use Microlib which does not use semihosting.

Now why the toolchain builds in libraries that use semihosting when MDK-ARM/uVision doesn't support semihhosting beats me..