bt_bitfield_write(target.ll, unsigned long long, s, l, src);
bt_bitfield_read(target.c, unsigned char, s, l, &readval);
if (readval != src) {
bt_bitfield_write(target.ll, unsigned long long, s, l, src);
bt_bitfield_read(target.c, unsigned char, s, l, &readval);
if (readval != src) {