HelenOS sources
DP_RSAR1 125 uspace/drv/nic/ne2k/dp8390.c pio_write_8(ne2k->port + DP_RSAR1, (addr >> 8) & 0xff);
DP_RSAR1 150 uspace/drv/nic/ne2k/dp8390.c pio_write_8(ne2k->port + DP_RSAR1, (addr >> 8) & 0xff);
DP_RSAR1 226 uspace/drv/nic/ne2k/dp8390.c pio_write_8(ne2k->port + DP_RSAR1, 0);
DP_RSAR1 244 uspace/drv/nic/ne2k/dp8390.c pio_write_8(ne2k->port + DP_RSAR1, 0);
DP_RSAR1 514 uspace/drv/nic/ne2k/dp8390.c pio_write_8(ne2k->port + DP_RSAR1, (offset >> 8) & 0xff);
HelenOS homepage, sources at GitHub