AX_MEDIUM_FD
(AX_MEDIUM_PS | AX_MEDIUM_FD | AX_MEDIUM_AC | \
(AX_MEDIUM_FD | AX_MEDIUM_PS | \
mode |= AX_MEDIUM_FD;
mode &= ~AX_MEDIUM_FD;
m |= duplex ? AX_MEDIUM_FD : 0;
mode &= ~AX_MEDIUM_FD;