1 files changed, 5 insertions, 2 deletions
diff --git a/c/src/lib/libcpu/powerpc/ppc403/console/console.c b/c/src/lib/libcpu/powerpc/ppc403/console/console.c
index 58d0138398..0e74879947 100644
--- a/c/src/lib/libcpu/powerpc/ppc403/console/console.c
+++ b/c/src/lib/libcpu/powerpc/ppc403/console/console.c
@@ -271,8 +271,11 @@ spiPollRead (int minor)
 static int
 spiInterruptWrite (int minor, const char *buf, int len)
 {
-  port->SPTB = *buf;           /* write char to send         */
-  port->SPTC |= TCRIntEnabled; /* always enable tx interrupt */
+  if (len > 0) {
+    port->SPTB = *buf;           /* write char to send         */
+    port->SPTC |= TCRIntEnabled; /* always enable tx interrupt */
+  }
+
   return 0;
 }