IB_ISA1
} while (MFP->mf_iprb & IB_ISA1);
single_inst_bset_b(MFP->mf_imrb, IB_ISA1);
single_inst_bset_b(MFP->mf_imrb, IB_ISA1);
single_inst_bset_b(MFP->mf_ierb, IB_ISA1);
single_inst_bclr_b(MFP->mf_imrb, IB_ISA1);
MFP->mf_iprb = (u_int8_t)~IB_ISA1;