SBD_BUSY
ret = SBD_BUSY;
if (sret == SBD_BUSY) {
} while (sret == SBD_BUSY);
if (sret == SBD_BUSY) {
if (sret == SBD_BUSY) {
if (sret == SBD_BUSY) {
if (sret == SBD_BUSY) {
sret = SBD_BUSY;