root@AR9331:/# cat /proc/mtd
dev:    size   erasesize  name
mtd0: 00020000 00010000 "u-boot"
mtd1: 000e214c 00010000 "kernel"
mtd2: 006edeb4 00010000 "rootfs"
mtd3: 00450000 00010000 "rootfs_data"
mtd4: 00010000 00010000 "art"
mtd5: 007d0000 00010000 "firmware"
root@AR9331:/#
root@AR9331:/# cd /tmp/
root@AR9331:/tmp# mkdir bin
root@AR9331:/tmp# cd bin/
root@AR9331:/tmp/bin# ls -l
root@AR9331:/tmp/bin# dd if=/dev/mtd0 of=uboot.bin
256+0 records in
256+0 records out
root@AR9331:/tmp/bin# dd if=/dev/mtd5 of=firmware.bin
16000+0 records in
16000+0 records out
root@AR9331:/tmp/bin# dd if=/dev/mtd4 of=art.bin
128+0 records in
128+0 records out
root@AR9331:/tmp/bin# cat uboot.bin firmware.bin art.bin > compilers.bin
root@AR9331:/tmp/bin# ls
art.bin        compilers.bin  firmware.bin   uboot.bin
root@AR9331:/tmp/bin# ls -lh
-rw-r--r--    1 root     root       64.0K Jul 17 17:34 art.bin
-rw-r--r--    1 root     root        8.0M Jul 17 17:35 compilers.bin
-rw-r--r--    1 root     root        7.8M Jul 17 17:34 firmware.bin
-rw-r--r--    1 root     root      128.0K Jul 17 17:34 uboot.binroot@AR9331:/# cat