SELBUSB
cur_channel = (sblkctl & SELBUSB)
sblkctl ^ SELBUSB);
&& ((ahc_inb(ahc, SBLKCTL) & SELBUSB) != 0))
ahc_outb(ahc, SBLKCTL, ahc_inb(ahc, SBLKCTL) ^ SELBUSB);
ahc_outb(ahc, SBLKCTL, ahc_inb(ahc, SBLKCTL) ^ SELBUSB);
ahc_outb(ahc, SBLKCTL, sblkctl | SELBUSB);
ahc_outb(ahc, SBLKCTL, sblkctl & ~SELBUSB);
sblkctl = ahc_inb(ahc, SBLKCTL) & (SELBUSB|SELWIDE);
sblkctl &= ~SELBUSB;
case SELBUSB:
ahc_outb(ahc, SBLKCTL, sblkctl | SELBUSB);
ahc_outb(ahc, SBLKCTL, sblkctl & ~SELBUSB);
ahc_outb(ahc, SBLKCTL, ahc_inb(ahc, SBLKCTL) | SELBUSB);
ahc_outb(ahc, SBLKCTL, ahc_inb(ahc, SBLKCTL) & ~SELBUSB);
&& ((sblkctl & SELBUSB) != 0))
ahc_outb(ahc, SBLKCTL, sblkctl ^ SELBUSB);
cur_channel = (sblkctl & SELBUSB)
sblkctl ^ SELBUSB);