added a 3-instruction 10-character echo test to examples

README.md

@@ -252,6 +252,8 @@ namely:
   (requires I/O port 1 support),
 * [FizzBuzz classic program](examples/fizzbuzz.mu8a)
   (requires I/O port 1 support),
+* [A simple 10-character echo test](examples/echo.mu8a) (requires both I/O
+  port 1 and port 2 support),
 * [Bulls and Cows game](examples/moo.mu8a),
 * [Lunar Lander game](examples/lunar.mu8a).
 

examples/assembled/echo.mu8

@@ -0,0 +1,3 @@
+1 5 10 0 11
+2 4 1 10 2
+3 3 1 11 1

examples/echo.mu8a

@@ -0,0 +1,3 @@
+set 10 0 11 ; set the newline character to loc 11
+inp 1 10 2  ; input characters from loc 1 to loc 10 from port 2
+out 1 11 1  ; output them right away along with the newline into port 1