diff --git a/abstract-machine/am/src/platform/nemu/ioe/gpu.c b/abstract-machine/am/src/platform/nemu/ioe/gpu.c
index 1910c0e..59cc0be 100644
--- a/abstract-machine/am/src/platform/nemu/ioe/gpu.c
+++ b/abstract-machine/am/src/platform/nemu/ioe/gpu.c
@@ -31,9 +31,10 @@ void __am_gpu_config(AM_GPU_CONFIG_T *cfg) {
 
 void __am_gpu_fbdraw(AM_GPU_FBDRAW_T *ctl) {
   GET_W(w);
+  uint32_t fb_addr = FB_ADDR;
   for (int i = 0; i < ctl->h; i++) {
     for (int j = 0; j < ctl->w; j++) {
-      outl((uint32_t)FB_ADDR + ((ctl->y + i) * w + (ctl->x + j)), (uint32_t)ctl->pixels + (w * i + j));
+      outl((uint32_t)fb_addr + ((ctl->y + i) * w + (ctl->x + j)), (uint32_t)ctl->pixels + (w * i + j));
     }
   }
   if (ctl->sync) {