diff --git a/abstract-machine/am/src/platform/nemu/ioe/gpu.c b/abstract-machine/am/src/platform/nemu/ioe/gpu.c
index 9cc28d6..eed7a88 100644
--- a/abstract-machine/am/src/platform/nemu/ioe/gpu.c
+++ b/abstract-machine/am/src/platform/nemu/ioe/gpu.c
@@ -35,8 +35,8 @@ void __am_gpu_fbdraw(AM_GPU_FBDRAW_T *ctl) {
   for (int i = 0; i < ctl->h; i++) {
     for (int j = 0; j < ctl->w; j++) {
       outl((uintptr_t)(fb_addr + 
-        ((ctl->y + i) * w + (ctl->x + j))),
-        ((uint32_t*)ctl->pixels)[w * i + j]);
+        (w * (ctl->y + i) + ctl->x + j)),
+        ((uint32_t*)ctl->pixels)[ctl->w * i + j]);
     }
   }
   if (ctl->sync) {