How many blocks to ignore:
skip=1 for if
seek=1 for of
backup mbr:
dd if=/dev/sda of=mbr bs=512 count=1
get partition table in mbr:
dd if=mbr of=dpt bs=1 skip=446 count=64
write image to floppy:
dd bs=512 if=Image of=/dev/fd0
原文：https://www.cnblogs.com/xinyueliu/p/12731876.html