configTOTAL_HEAP_SIZE increase

Posted by kkoovalsky on January 31, 2017
I’m programming STM32F407VET which contains 192KB of RAM. Default value of configTOTALHEAPSIZE is (sizet)15360 (generated from CubeMX), so it’s 61,44 KB. So, why isn’t the rest of RAM used by default? Can I freely increase the size? I use heap4.c

configTOTAL_HEAP_SIZE increase

Posted by rtel on January 31, 2017
I’m not sure how 15.36K becomes 61.44K, but you can set configTOTALHEAPSIZE to anything you like, until you run out of RAM: http://www.freertos.org/a00111.html

configTOTAL_HEAP_SIZE increase

Posted by kkoovalsky on February 3, 2017
So, is the calculation good: (sizet)15,36K = 4 * 15,36K, because sizet on STM32 is 4B, isn’t it?

configTOTAL_HEAP_SIZE increase

Posted by rtel on February 3, 2017
Look where configTOTALHEAPSIZE is used. Line 106 at the time of writing. It is a char array. If configTOTALHEAPSIZE is 1000 the heap will be 1000 bytes: https://sourceforge.net/p/freertos/code/HEAD/tree/trunk/FreeRTOS/Source/portable/MemMang/heap_4.c