MAC_CONTROL_FDX
mctl |= MAC_CONTROL_FDX;
mctl &= ~MAC_CONTROL_FDX;
mctl |= MAC_CONTROL_FDX;
mctl &= ~MAC_CONTROL_FDX;
mctl |= MAC_CONTROL_FDX;
mctl &= ~MAC_CONTROL_FDX;
MAC_CONTROL_FDX);