Hi Oleg,
There are many up_allocateheap In the source tree…but an F7 on PX4 master has: And it does not use CONFIG_RAM_END (CONFIG_RAM_START+CONFIG_RAM_SIZE) I deleted them and it px4_fmuv5 still builds. I will clean that up when I get past the upgrade. David *From:* Oleg Evseev [mailto:ev.m...@gmail.com] *Sent:* Tuesday, August 04, 2020 1:04 PM *To:* dev@nuttx.apache.org *Subject:* Re: stm32f7 CONFIG_RAM understanding Hi David, As I see they are used to define: CONFIG_RAM_END (CONFIG_RAM_START+CONFIG_RAM_SIZE) which in turn is used in heap allocation (up_allocateheap). By the way I am working with px4 master and custom board stm32f767 (software very close and based on fmu-v5). And I used CONFIG_RAM_SIZE=376832 CONFIG_RAM_START=0x20020000 but on reboots start to get random hardfaults (looking on address in log points to heap allocation functions) and sometimes fails advertising uorb topics (also heap allocation problem as I see). While I'm investigating this I notice this difference with RAM size config and ask this question (of course it may not be related to my issue). вт, 4 авг. 2020 г. в 22:49, David Sidrane <david.sidr...@nscdg.com>: Both are not used in the source. I would assume it is a legacy C&P from the F4, that should be removed. *From:* Oleg Evseev [mailto:ev.m...@gmail.com] *Sent:* Tuesday, August 04, 2020 12:45 PM *To:* dev@nuttx.apache.org *Subject:* Re: stm32f7 CONFIG_RAM understanding No, internal memory. For all boards stm32f769i-disco\ stm32f746-ws\ stm32f746g-disco\ nucleo-144\ but just found that except stm32f769i-disco, it understandably defines params for SRAM1 368Kb according to MCU memory map CONFIG_RAM_SIZE=376832 CONFIG_RAM_START=0x20020000 вт, 4 авг. 2020 г. в 22:27, Gregory Nutt <spudan...@gmail.com>: External SRAM? On 8/4/2020 1:08 PM, Oleg Evseev wrote: Hi, I wonder why stm32f7 boards has such RAM parameters in defconfigs: CONFIG_RAM_SIZE=245760 CONFIG_RAM_START=0x20010000 Where do these numbers come from while memory map is this? [image: изображение.png] --- With regards, Oleg
