MCR_RTS
outb(COMPORT + com_mcr, MCR_RTS | MCR_DTR);
if ((com->state & CS_RTS_IFLOW) && !(com->mcr_image & MCR_RTS) &&
outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
com->mcr_image &= ~MCR_RTS);
outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
if (com->mcr_image & MCR_RTS && com->state & CS_RTS_IFLOW)
outb(com->modem_ctl_port, com->mcr_image &= ~MCR_RTS);
if (!(com->mcr_image & MCR_RTS) && com->iptr < com->ihighwater
outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
if (mcr & MCR_RTS)
mcr |= MCR_RTS;
outb(iobase + com_mcr, (sp->mcr & MCR_IENABLE) | MCR_DTR | MCR_RTS);
outb(iobase + com_mcr, sp->mcr | MCR_DTR | MCR_RTS);