diff --git a/Mac/Lib/test/ctbtest.py b/Mac/Lib/test/ctbtest.py
new file mode 100644
index 0000000..d6847d3
--- /dev/null
+++ b/Mac/Lib/test/ctbtest.py
@@ -0,0 +1,41 @@
+#
+# Simple test program for ctb module: emulate a terminal.
+#
+import ctb
+import macconsole
+import sys
+
+def cb(err):
+	print 'Done, err=', err
+
+def main():
+	if not ctb.available():
+		print 'Communications Toolbox not available'
+		sys.exit(1)
+#	c = macconsole.copen('Terminal window')
+	print 'Minimal terminal emulator V1.0'
+	print '(type @ to exit)'
+	print
+	c = macconsole.fopen(sys.stdin)
+	f = sys.stdin
+	c.setmode(macconsole.C_RAW)
+	
+	l = ctb.CMNew('Serial Tool', None)
+	l.Open(0)
+	
+	while 1:
+		l.Idle()
+		d = f.read(1)
+		if d == '@':
+			break
+		if d:
+			l.Write(d, ctb.cmData, -1, 0)
+		l.Idle()
+		d, dummy = l.Read(1000, ctb.cmData, 0)
+		if d:
+			f.write(d)
+			f.flush()
+	l.Close(-1, 1)
+	del l
+			
+main()
\ No newline at end of file