# Is the software stack big enough? **URL:** \ **Category:** Kernel\ **Created:** [March 3, 2011, 2:41pm UTC](https://forums.freertos.org/t/is-the-software-stack-big-enough/4189 "2011-03-03T14:41:58Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![system](https://d2v6vdsk2p900z.cloudfront.net/original/1X/7fc8fdb729c645aab5b20282bbe34e57cb407be6.jpeg) [@system](https://forums.freertos.org/u/system)\ **Post date:** [March 3, 2011, 2:41pm UTC](https://forums.freertos.org/t/is-the-software-stack-big-enough/4189/1 "2011-03-03T14:41:58Z")
**[sandervh18](https://sourceforge.net/u/sandervh18/)** wrote on [Thursday, March 03, 2011](https://sourceforge.net/p/freertos/discussion/382005/thread/b94a738d/#bf7c): My device: PIC18F4550, software-environment MPLAB IDE I have a question concerning the software stack size. In the linkerfile there is STACK SIZE=0x60 RAM=BIG\_BLOCK, so there are 96 places. But in the FreeRTOSconfig.h file there is this value  #define configMINIMAL\_STACK\_SIZE ( 105 ) 1. why is the size in the linkerfile smaller than the configminimalstacksize? 2. when i count, how many bytes we need i get this: i think, probably wrong because thousands of people calculated it before me, the calculation is like this: 3 dummies for debugging 2 for address parameters 1 empty space 16  for WREG,status,intcon, bsr, fsr2L,…, pclath 20 for .tmpdata and math\_data 2 for top global data section 3 for the address of the task on the stack 1 for number of return addresses 1 for afterwards topofstack++ ±- 49 and if we want to save a whole hardware stack we need 139 bytes for the software stack of 1 task. So actually i don’t have any clue how the minimal stacksize is 105, but i think you do, would you mind to tell me? It would be very kind if someone could see to my questions 🙂 thanks! Kind regards, Sander ---
**Author:** ![system](https://d2v6vdsk2p900z.cloudfront.net/original/1X/7fc8fdb729c645aab5b20282bbe34e57cb407be6.jpeg) [@system](https://forums.freertos.org/u/system)\ **Post date:** [March 4, 2011, 4:33pm UTC](https://forums.freertos.org/t/is-the-software-stack-big-enough/4189/2 "2011-03-04T16:33:24Z")
**[sandervh18](https://sourceforge.net/u/sandervh18/)** wrote on [Friday, March 04, 2011](https://sourceforge.net/p/freertos/discussion/382005/thread/b94a738d/#15e3): Mmm i made a mistake, software stack is not the same as the allocated space per task. Still i want to know the answer of the second question, why a configMINIMAL\_STACK\_SIZE of 105? Thanks for the replies.