diff --git a/epicardium/modules/fatfs_fileops.c b/epicardium/modules/fatfs_fileops.c
index b7254440ffb499e38d2ebf801cf9b4cd31890266..de083fcb432581d8a79129d82a8828637fe57dfc 100644
--- a/epicardium/modules/fatfs_fileops.c
+++ b/epicardium/modules/fatfs_fileops.c
@@ -117,6 +117,7 @@ static inline bool parse_mode(const char *mstring, int *mode)
 		case 'w': //fallthrough intentional
 		case 'a': //fallthrough intentional
 		case 'x': //fallthrough intentional
+		case 'b': //fallthrough intentional
 			break;
 		default:
 			return false;