1 files changed, 3 insertions, 1 deletions
diff --git a/fw/fe310/bsp/gloss/sys_read.c b/fw/fe310/bsp/gloss/sys_read.c
index 1857fc6..cc14f2a 100644
--- a/fw/fe310/bsp/gloss/sys_read.c
+++ b/fw/fe310/bsp/gloss/sys_read.c
@@ -4,11 +4,13 @@
 
 #include "platform.h"
 
+#include "soc/uart.h"
+
 /* Read from a file.  */
 ssize_t
 _read(int fd, void *ptr, size_t len)
 {
-  if (fd != STDIN_FILENO) {
+  if ((fd != STDIN_FILENO) || !eos_uart_enabled()) {
     errno = ENOSYS;
     return -1;
   }