diff --git a/ChangeLog b/ChangeLog
index 9d94619f..ccd114d0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -19,6 +19,8 @@
 	* par.c: (Ditto.)
 	* pgm.c: (Ditto.)
 	* safemode.c: (Ditto.)
+	* serbb_posix.c: (Ditto.)
+	* serbb_win32.c: (Ditto.)
 	* stk500.c: (Ditto.)
 	* stk500v2.c: (Ditto.)
 	* term.c: (Ditto.)
diff --git a/serbb_posix.c b/serbb_posix.c
index 17337430..ea188375 100644
--- a/serbb_posix.c
+++ b/serbb_posix.c
@@ -305,6 +305,8 @@ void serbb_initpgm(PROGRAMMER *pgm)
   pgm->setpin         = serbb_setpin;
   pgm->getpin         = serbb_getpin;
   pgm->highpulsepin   = serbb_highpulsepin;
+  pgm->read_byte      = avr_read_byte_default;
+  pgm->write_byte     = avr_write_byte_default;
 }
 
 #endif  /* WIN32NATIVE */
diff --git a/serbb_win32.c b/serbb_win32.c
index 6bedb63a..ed1e8d8a 100644
--- a/serbb_win32.c
+++ b/serbb_win32.c
@@ -368,6 +368,8 @@ void serbb_initpgm(PROGRAMMER *pgm)
   pgm->setpin         = serbb_setpin;
   pgm->getpin         = serbb_getpin;
   pgm->highpulsepin   = serbb_highpulsepin;
+  pgm->read_byte      = avr_read_byte_default;
+  pgm->write_byte     = avr_write_byte_default;
 }
 
 #endif  /* WIN32NATIVE */