This was tested on Meadow F7Micro (board: stm32f777zit6-meadow). This board has an IS42S16160J-7BLI SDRAM chip (16Mx16 at 166MHz) connected to FMC bus.
Initial test of 1MiB:
NuttShell (NSH)
nsh> ?
help usage: help [-v] [<cmd>]
. cp env kill printf test uptime
[ cmp exec ls pwd time usleep
? dirname exit mkdir rm true xd
basename dd false mkrd rmdir truncate
break df free mksmartfs set uname
cat dmesg help mount sleep umount
cd echo hexdump mv source unset
Builtin Apps:
flash_eraseall nsh ramtest sh
nsh> ramtest -w 0xc0000000 1024
RAMTest: Marching ones: c0000000 1024
RAMTest: Marching zeroes: c0000000 1024
RAMTest: Pattern test: c0000000 1024 55555555 aaaaaaaa
RAMTest: Pattern test: c0000000 1024 66666666 99999999
RAMTest: Pattern test: c0000000 1024 33333333 cccccccc
RAMTest: Address-in-address test: c0000000 1024Testing 8MiB:
nsh> ramtest -w 0xc0000000 8388608
RAMTest: Marching ones: c0000000 8388608
RAMTest: Marching zeroes: c0000000 8388608
RAMTest: Pattern test: c0000000 8388608 55555555 aaaaaaaa
RAMTest: Pattern test: c0000000 8388608 66666666 99999999
RAMTest: Pattern test: c0000000 8388608 33333333 cccccccc
RAMTest: Address-in-address test: c0000000 8388608
nsh>Testing 16MiB:
nsh> ramtest -w 0xc0000000 16777216
RAMTest: Marching ones: c0000000 16777216
RAMTest: Marching zeroes: c0000000 16777216
RAMTest: Pattern test: c0000000 16777216 55555555 aaaaaaaa
RAMTest: Pattern test: c0000000 16777216 66666666 99999999
RAMTest: Pattern test: c0000000 16777216 33333333 cccccccc
RAMTest: Address-in-address test: c0000000 16777216
nsh>Testing 32MiB:
nsh> ramtest -w 0xc0000000 33554432
RAMTest: Marching ones: c0000000 33554432
RAMTest: Marching zeroes: c0000000 33554432
RAMTest: Pattern test: c0000000 33554432 55555555 aaaaaaaa
RAMTest: Pattern test: c0000000 33554432 66666666 99999999
RAMTest: Pattern test: c0000000 33554432 33333333 cccccccc
RAMTest: Address-in-address test: c0000000 33554432
nsh>