vrpiu_buf_read
vrpiu_buf_read(sc, PIUAB(0));
vrpiu_buf_read(sc, PIUAB(1));
vrpiu_buf_read(sc, PIUAB(2));
tpx0 = vrpiu_buf_read(sc, PIUPB(page, 0));
tpx1 = vrpiu_buf_read(sc, PIUPB(page, 1));
tpy0 = vrpiu_buf_read(sc, PIUPB(page, 2));
tpy1 = vrpiu_buf_read(sc, PIUPB(page, 3));
vrpiu_buf_read(sc, PIUPB(page, i));