CL_SEQR1E
old1e = vga_rseq(cinfo->regbase, CL_SEQR1E) & ~0x1;
vga_wseq(cinfo->regbase, CL_SEQR1E, old1e);
vga_wseq(regbase, CL_SEQR1E, nom);
vga_wseq(regbase, CL_SEQR1E, tmp);