artificial horizon

src/main/config/config.c

@@ -432,6 +432,8 @@ static void resetConf(void)
     masterConfig.osdProfile.item_pos[OSD_VOLTAGE_WARNING]    = -80;
     masterConfig.osdProfile.item_pos[OSD_ARMED]              = -107;
     masterConfig.osdProfile.item_pos[OSD_DISARMED]           = -109;
+    masterConfig.osdProfile.item_pos[OSD_ARTIFICIAL_HORIZON] = 1;
+    masterConfig.osdProfile.item_pos[OSD_HORIZON_SIDEBARS]   = -1;
 #endif
 
 #ifdef USE_RTC6705

src/main/drivers/max7456.c

@@ -38,6 +38,11 @@
 
 static IO_t max7456CsPin = IO_NONE;
 
+/** Artificial Horizon limits **/
+#define AHIPITCHMAX 200             // Specify maximum AHI pitch value displayed. Default 200 = 20.0 degrees
+#define AHIROLLMAX  400             // Specify maximum AHI roll value displayed. Default 400 = 40.0 degrees
+#define AHISIDEBARWIDTHPOSITION 7
+#define AHISIDEBARHEIGHTPOSITION 3
 
 uint16_t max_screen_size;
 uint8_t  video_signal_type = 0;
@@ -127,14 +132,49 @@ void max7456_write_string(const char *string, int16_t address) {
     char *dest;
 
     if (address >= 0)
-        dest  = screen + address;
+        dest  = max7456_screen + address;
     else
-        dest  = screen + (max_screen_size + address);
+        dest  = max7456_screen + (max_screen_size + address);
 
-    while(*string && dest < (screen + max_screen_size))
+    while(*string && dest < (max7456_screen + max_screen_size))
         *dest++ = *string++;
 }
 
+
+// Write the artifical horizon to the screen buffer
+void max7456_artificial_horizon(int rollAngle, int pitchAngle, uint8_t show_sidebars) {
+    uint16_t position = 194;
+
+    if(pitchAngle>AHIPITCHMAX) pitchAngle=AHIPITCHMAX;
+    if(pitchAngle<-AHIPITCHMAX) pitchAngle=-AHIPITCHMAX;
+    if(rollAngle>AHIROLLMAX) rollAngle=AHIROLLMAX;
+    if(rollAngle<-AHIROLLMAX) rollAngle=-AHIROLLMAX;
+
+    for(uint8_t X=0; X<=8; X++) {
+      if (X==4) X=5;
+      int Y = (rollAngle * (4-X)) / 64;
+      Y -= pitchAngle / 8;
+      Y += 41;
+      if(Y >= 0 && Y <= 81) {
+        uint16_t pos = position -7 + LINE*(Y/9) + 3 - 4*LINE + X;
+        max7456_screen[pos] = SYM_AH_BAR9_0+(Y%9);
+      }
+    }
+
+    if (show_sidebars) {
+      // Draw AH sides
+      int8_t hudwidth =  AHISIDEBARWIDTHPOSITION;
+      int8_t hudheight = AHISIDEBARHEIGHTPOSITION;
+      for(int8_t X=-hudheight; X<=hudheight; X++) {
+        max7456_screen[position-hudwidth+(X*LINE)] = SYM_AH_DECORATION;
+        max7456_screen[position+hudwidth+(X*LINE)] = SYM_AH_DECORATION;
+      }
+      // AH level indicators
+      max7456_screen[position-hudwidth+1] =  SYM_AH_LEFT;
+      max7456_screen[position+hudwidth-1] =  SYM_AH_RIGHT;
+    }
+}
+
 void max7456_draw_screen(void) {
     uint16_t xx;
     if (!max7456_lock) {

src/main/drivers/max7456.h

@@ -149,5 +149,6 @@ char max7456_screen[VIDEO_BUFFER_CHARS_PAL];
 void max7456_init(uint8_t system);
 void max7456_draw_screen(void);
 void max7456_draw_screen_fast(void);
+void max7456_artificial_horizon(int rollAngle, int pitchAngle, uint8_t show_sidebars);
 void max7456_write_string(const char *string, int16_t address);
 void max7456_write_nvm(uint8_t char_address, uint8_t *font_data);

src/main/io/osd.c

@@ -699,6 +699,9 @@ void updateOsd(void)
             if (masterConfig.osdProfile.item_pos[OSD_CPU_LOAD] != -1) {
                 print_average_system_load(masterConfig.osdProfile.item_pos[OSD_CPU_LOAD], 0);
             }
+            if (masterConfig.osdProfile.item_pos[OSD_ARTIFICIAL_HORIZON] != -1) {
+                max7456_artificial_horizon(attitude.values.roll, attitude.values.pitch, masterConfig.osdProfile.item_pos[OSD_HORIZON_SIDEBARS] != -1);
+            }
         }
     } else {
         max7456_draw_screen_fast();

src/main/io/osd.h

@@ -48,6 +48,8 @@ typedef enum {
     OSD_VOLTAGE_WARNING,
     OSD_ARMED,
     OSD_DISARMED,
+    OSD_ARTIFICIAL_HORIZON,
+    OSD_HORIZON_SIDEBARS,
     OSD_MAX_ITEMS, // MUST BE LAST
 } osd_items_t;