IOP_ADDR_ALIVE
iop_write1(ioph, IOP_ADDR_ALIVE, 0);
do { c2 = iop_read1(ioph, IOP_ADDR_ALIVE); cs++; } while (c2 != 0xff);
alive = iop_read1(ioph, IOP_ADDR_ALIVE);
iop_write1(ioph, IOP_ADDR_ALIVE, 0);