How to monitor flash and RAM usage after compilation?

Question

Is there a window in Keil uVision available to monitor how much flash and RAM I've consumed? I'm not seeing anything in the build output and am not sure where else to look.

Håkon Alseth · Accepted Answer

The total RAM consumption is: 
 ZI-data + RW-data
 
 The total flash consumption is: 
 Code + RO-data + RW-data
 
 These values should be listed when you compile your project (atleast in Keil, use 'arm-none-eabi-size myapplication.out' for GCC) or located in the .map file generated by the compiler/linker. 
 Why is RW-data listed in RAM and code? This is because this section holds the non-zero initialized values. for instance: 
 static int g_test = 0xFF1234FF;
 
 This will consume 4 bytes of RAM, and 4 bytes of flash to store it's initial value (0xFF1234FF). 
 More details about RAM usage: 
 The total RAM consumption also holds the application stack for auto-variables, which variables inside a scope, such as int func(){int a; int b;} , where 'a' and 'b' here are auto-variables.
The default stack_size set in your arm_startup.s file is set to 2048 bytes. 
 If the stack grows outside it's area (2048 bytes in this case), meaning that your auto-variables in scope is greater than the stack_size set, you will run into a stack overflow.
if you google "stack usage monitoring" or similar you'll find methods for evaluating the stack usage for a given application. Note that the overall stack usage must be evaluated run-time, with the application running in all corner-cases. 
 Sorry if I've confused you,
Håkon

How to monitor flash and RAM usage after compilation?

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