diff --git a/src/fileio.c b/src/fileio.c
index e6d5c037..9c3313b2 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -37,6 +37,9 @@
 #ifndef EM_AVR32
 #  define EM_AVR32 0x18ad         /* unofficial */
 #endif
+#ifndef EM_AVR
+#  define EM_AVR 83               /* OpenBSD lacks it */
+#endif
 #endif
 
 #include "avrdude.h"