emul/sms: don't hardcode name table offset

Use reg 2 as specified.

emul/hw/sms/vdp.c

@@ -61,7 +61,8 @@ uint8_t vdp_pixel(VDP *vdp, uint16_t x, uint16_t y)
         return 0;
     }
     // name table offset
-    uint16_t offset = 0x3800 + ((y/8) << 6) + ((x/8) << 1);
+    uint16_t offset = (vdp->regs[2] & 0xe) << 10;
+    offset += ((y/8) << 6) + ((x/8) << 1);
     uint16_t tableval = vdp->vram[offset] + (vdp->vram[offset+1] << 8);
     uint16_t tilenum = tableval & 0x1ff;
     // is palette select bit on? if yes, use sprite palette instead

recipes/sms/blk/605

@@ -1,7 +1,7 @@
 CREATE _idat
 0b00000100 C, 0x80 C, ( Bit 2: Select mode 4 )
 0b00000000 C, 0x81 C,
-0b11111111 C, 0x82 C, ( Name table: 0x3800 )
+0b00001110 C, 0x82 C, ( Name table: 0x3800 )
 0b11111111 C, 0x85 C, ( Sprite table: 0x3f00 )
 0b11111111 C, 0x86 C, ( sprite use tiles from 0x2000 )
 0b11111111 C, 0x87 C, ( Border uses palette 0xf )