IRST
outb(SRST | IRST /*|SCRST */ , CONTROL(sh->io_port));
outb(IRST, CONTROL(sh->io_port));
outb(IRST, CONTROL(base));
SCR_JUMPR ^ IFTRUE (MASK (IRST, IRST)),
SCR_JUMPR ^ IFTRUE (MASK (IRST, IRST)),