diff --git a/abstract-machine/am/src/platform/nemu/ioe/gpu.c b/abstract-machine/am/src/platform/nemu/ioe/gpu.c
index 02d9850..0a43216 100644
--- a/abstract-machine/am/src/platform/nemu/ioe/gpu.c
+++ b/abstract-machine/am/src/platform/nemu/ioe/gpu.c
@@ -33,7 +33,7 @@ void __am_gpu_fbdraw(AM_GPU_FBDRAW_T *ctl) {
   GET_W(w);
   for (int i = 0; i < ctl->h; i++) {
     for (int j = 0; j < ctl->w; j++) {
-      outl((FB_ADDR + ((ctl->y + j) * w + (ctl->x + i)) * 4), ((uint32_t)ctl->pixels + w * j + i));
+      outl((uint32_t)FB_ADDR + ((ctl->y + j) * w + (ctl->x + i)), ((uint32_t)ctl->pixels + w * j + i));
     }
   }
   if (ctl->sync) {