hexdump
hexdump -vC -n 512 /dev/hda
000001d0 01 0d 83 fe ff ff cd 2f 03 00 f0 62 a9 03 00 fe |......./...b....| 000001e0 ff ff 82 fe ff ff bd 92 ac 03 fa e7 1d 00 00 00 |................| 000001f0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 55 aa |..............U.| 00000200
od
od -Ax -tx1 -N 512 /dev/hda
0001d0 01 0d 83 fe ff ff cd 2f 03 00 f0 62 a9 03 00 fe 0001e0 ff ff 82 fe ff ff bd 92 ac 03 fa e7 1d 00 00 00 0001f0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 55 aa 000200