> how do you manage the balancing of card use, or is there still a card firmware layer in the loop that does that?
The SD card is accessed as a ring buffer, so all addresses are written evenly. (It was my understanding that SD cards implement wear leveling themselves though, so the wear leveling should be free even if the SD card was written to randomly -- if my understanding is correct.)
> how do you handle memory dropouts for a given address/cell/whatever you call a memory location, or as above?
SD card write failures cause the firmware to crash and reset itself, so it'll try again when another photo is triggered. (It also logs the reset so it can be debugged.)
FWIW I'm using Samsung 128 GB "PRO Endurance" SD cards, with endurance == 820 TBW, which works out to 820e12 / 5.97e6 (size of one photo) == 137e6. So you can capture 137 million photos before the SD card is expected to fail.
The SD card is accessed as a ring buffer, so all addresses are written evenly. (It was my understanding that SD cards implement wear leveling themselves though, so the wear leveling should be free even if the SD card was written to randomly -- if my understanding is correct.)
> how do you handle memory dropouts for a given address/cell/whatever you call a memory location, or as above?
SD card write failures cause the firmware to crash and reset itself, so it'll try again when another photo is triggered. (It also logs the reset so it can be debugged.)
FWIW I'm using Samsung 128 GB "PRO Endurance" SD cards, with endurance == 820 TBW, which works out to 820e12 / 5.97e6 (size of one photo) == 137e6. So you can capture 137 million photos before the SD card is expected to fail.