xx

1 files changed, 7 insertions, 3 deletions

diff --git a/uart.c b/uart.c
index 659c574..b6271c1 100644
--- a/uart.c
+++ b/uart.c
@@ -49,11 +49,15 @@ uartputc(int c)
   *R(0) = c;
 }
 
-uint
+int
 uartgetc(void)
 {
-  // XXX this isn't right, must check there's data in the FIFO.
-  return *R(0);
+  if(*(5) & 0x01){
+    // input data is ready.
+    return *R(0);
+  } else {
+    return -1;
+  };
 }
 
 void