Added a new debugging channel io to allow read/writes on a port to be
logged to a file.

diff --git a/include/debugdefs.h b/include/debugdefs.h
index 3313d2d..42e6c92 100644
--- a/include/debugdefs.h
+++ b/include/debugdefs.h
@@ -4,7 +4,7 @@
 #include "debugtools.h"
 #endif
 
-#define DEBUG_CHANNEL_COUNT 147
+#define DEBUG_CHANNEL_COUNT 148
 #ifdef DEBUG_RUNTIME
 short debug_msg_enabled[][DEBUG_CLASS_COUNT] = {
 {1, 1, 0, 0},
@@ -154,6 +154,7 @@
 {1, 1, 0, 0},
 {1, 1, 0, 0},
 {1, 1, 0, 0},
+{1, 1, 0, 0},
 };
 const char* debug_ch_name[] = {
 "1",
@@ -219,6 +220,7 @@
 "int19",
 "int21",
 "int31",
+"io",
 "ipaddress",
 "key",
 "keyboard",