diff --git a/stm-firmware/boot/startup_stm32f4xx.S b/stm-firmware/boot/startup_stm32f4xx.S
index 9096057..0b9c10a 100644
--- a/stm-firmware/boot/startup_stm32f4xx.S
+++ b/stm-firmware/boot/startup_stm32f4xx.S
@@ -31,7 +31,7 @@
   */
     
   .syntax unified
-  .cpu cortex-m3
+  .cpu cortex-m4
   .fpu softvfp
   .thumb