diff --git a/boot/zephyr/prj.conf b/boot/zephyr/prj.conf
index f6d9342..caf48f9 100644
--- a/boot/zephyr/prj.conf
+++ b/boot/zephyr/prj.conf
@@ -1,6 +1,7 @@
 CONFIG_CONSOLE_HANDLER=y
 CONFIG_SYS_LOG=y
 CONFIG_DEBUG=y
+CONFIG_SYSTEM_CLOCK_DISABLE=y
 
 CONFIG_MAIN_STACK_SIZE=10240
 CONFIG_MBEDTLS=y