detect if OLED is plugged in

.gitmodules

 	url = https://github.com/raspberrypi/pico-sdk
 [submodule "firmware/pico-ssd1306"]
 	path = firmware/pico-ssd1306
-	url = https://github.com/daschr/pico-ssd1306/
+	url = https://github.com/xythobuz/pico-ssd1306

firmware/CMakeLists.txt

     -Wextra
     -Werror
     -Wshadow
+
+    -DSSD1306_DEBUG_PRINT=debug
+    -DSSD1306_DEBUG_INCLUDE="log.h"
 )
 
 # suppress some warnings for borked 3rd party files in Pico SDK

firmware/include/lcd.h

 #define FONT_WIDTH 5
 
 void lcd_init(void);
-void lcd_splash(void);
+void lcd_splash_version(void);
 
 #endif // __LCD_H__

firmware/pico-ssd1306

-Subproject commit 8467f5b06ebd7bfa7b53e4ebc83dfdc6f396e4eb
+Subproject commit 607fe1cc3c84d662f749e9af0355bc15de0fc48e

firmware/src/lcd.c

 static const uint gpio_num_i2c[2] = { 14, 15 };
 
 static ssd1306_t lcd = {0};
+static bool found = false;
 
 void lcd_init(void) {
     i2c_init(gpio_inst_i2c, 2UL * 1000UL * 1000UL);
         gpio_pull_up(gpio_num_i2c[i]);
     }
 
-    ssd1306_init(&lcd, LCD_WIDTH, LCD_HEIGHT, LCD_I2C_ADDR, gpio_inst_i2c);
+    found = ssd1306_init(&lcd, LCD_WIDTH, LCD_HEIGHT, LCD_I2C_ADDR, gpio_inst_i2c);
+
+    if (found) {
+        debug("SSD1306 OLED is connected");
+    } else {
+        debug("No SSD1306 OLED found!");
+    }
 }
 
-void lcd_splash(void) {
+void lcd_splash_version(void) {
+    if (!found) {
+        return;
+    }
+
     ssd1306_clear(&lcd);
 
     ssd1306_draw_string(&lcd, 0, 0, 2,

firmware/src/main.c

 
     buttons_init();
     lcd_init();
-    lcd_splash();
+    lcd_splash_version();
 
     debug("go");