PL_PCM_SIGNAL
if (inpw(PLC(np,PL_STATUS_B)) & PL_PCM_SIGNAL) {
if (inpw(PLC(np,PL_STATUS_B)) & PL_PCM_SIGNAL) {
if (!(inpw(PLC(np,PL_STATUS_B)) & PL_PCM_SIGNAL))
!(inpw(PLC(np,PL_STATUS_B)) & PL_PCM_SIGNAL))