Someone showed me a photo and datasheet of a Acekard 2i hw 81 PCB that had a 16mbit SST flash chip on it:
Currently when using the backup options ntrboot flasher (which uses this as it's submodule) is producing 16Mbyte bin files (which is 128Mbits and that is about 5 times the actual capacity of the chip!)...this appears to be incorrect and was why i was getting inconsistent results trying to flash backups to my Acekard 2i! After I trimmed my backup to 2mbytes it worked perfectly every time! (since in that instance I was using DSi version of ntrbootflasher which doesn't try to read the entire file into ram first so it doesn't error out until it finishes flashing 2Mbytes of the flash and goes to try and read more data but stops because the file isn't larger then 2MBytes)
I recommend the flash dump/write size for hw 81 be revised to the correct value of 2mbytes. I suspect whom ever did the original code base for the acekard write code incorrectly set the read/write size to 16Mbyte when reading the spec sheet. The spec sheet for that SST chip indicates it to be 16mbit which == 2Mbytes but whom ever was writing the flash code might mistook that for 16Mbytes. :P
This has likely resulted in a lot of issues for folks trying to use the backup restore feature. (and probably a lot of failed attempts to convert certain Acekard 2i clones into 2i's and visa versa) This issue mainly doesn't impact ntrboot injection process since I'm pretty sure in that instance most normal ntrboot payloads never have to be written past the 2MByte barrier and versions ntrbootflasher I know of only flashes the regions it needs to in that instance. But this incorrect flash size can cause unintended behavior when doing a backup restore.
Unless there is any known instances of hw 81's having larger flash chips I would recommend setting the flash read/write size for the backup menu to be 2Mbyte instead of 16Mbyte.
Someone showed me a photo and datasheet of a Acekard 2i hw 81 PCB that had a 16mbit SST flash chip on it:
Currently when using the backup options ntrboot flasher (which uses this as it's submodule) is producing 16Mbyte bin files (which is 128Mbits and that is about 5 times the actual capacity of the chip!)...this appears to be incorrect and was why i was getting inconsistent results trying to flash backups to my Acekard 2i! After I trimmed my backup to 2mbytes it worked perfectly every time! (since in that instance I was using DSi version of ntrbootflasher which doesn't try to read the entire file into ram first so it doesn't error out until it finishes flashing 2Mbytes of the flash and goes to try and read more data but stops because the file isn't larger then 2MBytes)
I recommend the flash dump/write size for hw 81 be revised to the correct value of 2mbytes. I suspect whom ever did the original code base for the acekard write code incorrectly set the read/write size to 16Mbyte when reading the spec sheet. The spec sheet for that SST chip indicates it to be 16mbit which == 2Mbytes but whom ever was writing the flash code might mistook that for 16Mbytes. :P
This has likely resulted in a lot of issues for folks trying to use the backup restore feature. (and probably a lot of failed attempts to convert certain Acekard 2i clones into 2i's and visa versa) This issue mainly doesn't impact ntrboot injection process since I'm pretty sure in that instance most normal ntrboot payloads never have to be written past the 2MByte barrier and versions ntrbootflasher I know of only flashes the regions it needs to in that instance. But this incorrect flash size can cause unintended behavior when doing a backup restore.
Unless there is any known instances of hw 81's having larger flash chips I would recommend setting the flash read/write size for the backup menu to be 2Mbyte instead of 16Mbyte.