Hello TI Forum,
I am developing an application that uses a TM4C129 microcontroller. At certain points, I would like the microcontroller to enter the lowest power mode possible while still retaining the SRAM. After reading the datasheet, I still can't tell what power configuration to use. I know that the hibernation module has 16 32-bit words of battery backed memory, but I need more memory than that. The datasheet isn't 100% clear which low-power modes will wipe the SRAM and which will retain it, so I'm hoping someone can help me figure this out.
Based on my reading, I don't think I want hibernation mode, because RAM appears to be lost. However, hibernation + VDD3ON mode seems to at least retain GPIO pin states, so maybe it also saves all RAM? But I'm not sure.
Bonus question: if the voltage drops low enough, will the microcontroller automatically turn off and erase everything before the voltage drops low enough to corrupt the RAM? Or do I need to worry about that myself? I'm concerned about the situation where the backup voltage droops so low the RAM gets corrupted, and then when primary power is reapplied, the microcontroller thinks it has valid data, but it's actually corrupted. Ideally, I'd like to retain the RAM for as long as possible, but wipe it if I hit some low-voltage threshold. That way, when primary power is applied, I either have valid data that was retained, or no data at all.
Thanks!