summaryrefslogtreecommitdiff
path: root/vdp.c
diff options
context:
space:
mode:
Diffstat (limited to 'vdp.c')
-rw-r--r--vdp.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/vdp.c b/vdp.c
index 76aea0d..35b0acb 100644
--- a/vdp.c
+++ b/vdp.c
@@ -619,7 +619,7 @@ void read_map_scroll(uint16_t column, uint16_t vsram_off, uint32_t line, uint16_
vscroll <<= 1;
vscroll |= 1;
}
- vscroll &= (context->vsram[(context->regs[REG_MODE_3] & BIT_VSCROLL ? column : 0) + vsram_off] + line);
+ vscroll &= (context->vsram[(context->regs[REG_MODE_3] & BIT_VSCROLL ? (column-2)&63 : 0) + vsram_off] + line);
context->v_offset = vscroll & v_offset_mask;
//printf("%s | line %d, vsram: %d, vscroll: %d, v_offset: %d\n",(vsram_off ? "B" : "A"), line, context->vsram[context->regs[REG_MODE_3] & 0x4 ? column : 0], vscroll, context->v_offset);
vscroll >>= vscroll_shift;