DEFRDE
howmany(bpb.rde ? bpb.rde : DEFRDE,
howmany(DEFRDE, bpb.bps / sizeof(struct de)) +
bpb.rde = DEFRDE;
howmany(bpb.rde ? bpb.rde : DEFRDE,
howmany(DEFRDE, bpb.bps / sizeof(struct de)) +
bpb.rde = DEFRDE;