diff --git a/firmware/make.bat b/firmware/make.bat
index 5b2e3db..aa492b9 100644
--- a/firmware/make.bat
+++ b/firmware/make.bat
@@ -1,3 +1,5 @@
+if not exist strings.bin.zx7b echo > strings.bin.zx7b
+if not exist version.asm echo  define version 4 > version.asm
 sjasmplus firmware.asm
 fcut      firmware_strings.rom  7e00 -7e00  strings.bin
 zx7b      strings.bin           strings.bin.zx7b