From d8b7e4a199a1f6027260c1f60f9190dc1b69fa3c Mon Sep 17 00:00:00 2001
From: Randy Mackay <rmackay9@yahoo.com>
Date: Fri, 15 May 2015 13:24:18 +0900
Subject: [PATCH] Copter: add support for 4th mavlink channel

---
 ArduCopter/Parameters.h   | 1 +
 ArduCopter/Parameters.pde | 6 ++++++
 ArduCopter/system.pde     | 5 +++++
 3 files changed, 12 insertions(+)

diff --git a/ArduCopter/Parameters.h b/ArduCopter/Parameters.h
index 7991659b75..a366b057bb 100644
--- a/ArduCopter/Parameters.h
+++ b/ArduCopter/Parameters.h
@@ -193,6 +193,7 @@ public:
         k_param_ch11_option,
         k_param_ch12_option,     // 123
         k_param_takeoff_trigger_dz,
+        k_param_gcs3,            // 125
 
         //
         // 140: Sensor parameters
diff --git a/ArduCopter/Parameters.pde b/ArduCopter/Parameters.pde
index 99542d4055..18e90015db 100644
--- a/ArduCopter/Parameters.pde
+++ b/ArduCopter/Parameters.pde
@@ -884,6 +884,12 @@ const AP_Param::Info var_info[] PROGMEM = {
     GOBJECTN(gcs[2],  gcs2,       "SR2_",     GCS_MAVLINK),
 #endif
 
+#if MAVLINK_COMM_NUM_BUFFERS > 3
+    // @Group: SR3_
+    // @Path: GCS_Mavlink.pde
+    GOBJECTN(gcs[3],  gcs3,       "SR3_",     GCS_MAVLINK),
+#endif
+
     // @Group: AHRS_
     // @Path: ../libraries/AP_AHRS/AP_AHRS.cpp
     GOBJECT(ahrs,                   "AHRS_",    AP_AHRS),
diff --git a/ArduCopter/system.pde b/ArduCopter/system.pde
index f9b7842988..facbea5192 100644
--- a/ArduCopter/system.pde
+++ b/ArduCopter/system.pde
@@ -139,6 +139,11 @@ static void init_ardupilot()
     gcs[2].setup_uart(serial_manager, AP_SerialManager::SerialProtocol_MAVLink, 1);
 #endif
 
+#if MAVLINK_COMM_NUM_BUFFERS > 3
+    // setup serial port for fourth telemetry port (not used by default)
+    gcs[3].setup_uart(serial_manager, AP_SerialManager::SerialProtocol_MAVLink, 2);
+#endif
+
 #if FRSKY_TELEM_ENABLED == ENABLED
     // setup frsky
     frsky_telemetry.init(serial_manager);