diff --git a/platformio.ini b/platformio.ini
index c9eb6d5f4..04835d6c0 100755
--- a/platformio.ini
+++ b/platformio.ini
@@ -74,6 +74,7 @@ build_flags               = ${core_active.build_flags}
 build_unflags             = -Wall
 
 board_build.f_cpu         = 80000000L
+board_build.f_flash       = 40000000L
 monitor_speed             = 115200
 upload_speed              = 115200
 ; *** Upload Serial reset method for Wemos and NodeMCU