FDMFMSYNC
custom.dsksync = FDMFMSYNC;
*rp++ = (FDMFMSYNC << 16) | FDMFMSYNC;
while ((u_long *)sp < ep && *sp != FDMFMSYNC)
while ((u_long *)sp < ep && *sp == FDMFMSYNC)
*rp++ = FDMFMSYNC;
*rp++ = FDMFMSYNC;
*rp++ = FDMFMSYNC;
*rp++ = FDMFMSYNC;
*rp++ = FDMFMSYNC;
*rp++ = FDMFMSYNC;