From ba3cdf74b5d6acf37ff1bc2109d99fcd98e2d55e Mon Sep 17 00:00:00 2001
From: Andrew Tridgell <andrew@tridgell.net>
Date: Mon, 8 Jan 2018 18:12:21 +1100
Subject: [PATCH] HAL_Chibios: optional ADC debugging

this debugging capability is very useful on board bringup. It outputs
the first 6 analog channels as an AP_ADC MAVLink message
---
 libraries/AP_HAL_ChibiOS/AnalogIn.cpp | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/libraries/AP_HAL_ChibiOS/AnalogIn.cpp b/libraries/AP_HAL_ChibiOS/AnalogIn.cpp
index 11a1ad0f75..d4d29f8bfb 100644
--- a/libraries/AP_HAL_ChibiOS/AnalogIn.cpp
+++ b/libraries/AP_HAL_ChibiOS/AnalogIn.cpp
@@ -23,6 +23,13 @@
 extern AP_IOMCU iomcu;
 #endif
 
+#ifndef CHIBIOS_ADC_MAVLINK_DEBUG
+// this allows the first 6 analog channels to be reported by mavlink for debugging purposes
+#define CHIBIOS_ADC_MAVLINK_DEBUG 0
+#endif
+
+#include <GCS_MAVLink/GCS_MAVLink.h>
+
 #define ANLOGIN_DEBUGGING 0
 
 // base voltage scaling for 12 bit 3.3V ADC
@@ -274,6 +281,18 @@ void AnalogIn::_timer_tick(void)
     // now handle special inputs from IOMCU
     _servorail_voltage = iomcu.get_vservo();
 #endif
+
+#if CHIBIOS_ADC_MAVLINK_DEBUG
+    static uint8_t count;
+    if (AP_HAL::millis() > 5000 && count++ == 10) {
+        count = 0;
+        uint16_t adc[6] {};
+        for (uint8_t i=0; i < ADC_GRP1_NUM_CHANNELS; i++) {
+            adc[i] = buf_adc[i];
+        }
+        mavlink_msg_ap_adc_send(MAVLINK_COMM_0, adc[0], adc[1], adc[2], adc[3], adc[4], adc[5]);
+    }
+#endif
 }
 
 AP_HAL::AnalogSource* AnalogIn::channel(int16_t pin)