update ss_oled to 3.1.0

platformio.ini

@@ -58,7 +58,8 @@ lib_deps_lora =
     ;MCCI LoRaWAN LMIC library@>=3.1.0
     https://github.com/mcci-catena/arduino-lmic.git#5322dd1
 lib_deps_display =
-     ss_oled@=3.0.0
+     ;ss_oled@>=3.1.0
+     https://github.com/bitbank2/ss_oled.git#26f5d40
      BitBang_I2C@>=1.2.0
      QRCode@>=0.0.1
 lib_deps_matrix_display =

src/display.cpp

@@ -56,7 +56,12 @@ static const char TAG[] = __FILE__;
 const char *printmonth[] = {"xxx", "Jan", "Feb", "Mar", "Apr", "May", "Jun",
                             "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
 uint8_t DisplayIsOn = 0;
-uint8_t displaybuf[DISPLAY_WIDTH * DISPLAY_HEIGHT / 8] = {0};
+
+#ifdef USE_BACKBUFFER
+static uint8_t displaybuf[DISPLAY_WIDTH * DISPLAY_HEIGHT / 8] = {0};
+#else
+static uint8_t *displaybuf = NULL;
+#endif
 
 QRCode qrcode;
 
@@ -82,6 +87,9 @@ void init_display(bool verbose) {
     oledInit(OLED_128x64, true, false, -1, -1, 400000L);
 #endif
 
+    // set display buffer
+    oledSetBackBuffer(displaybuf);
+
     // clear display
     oledSetContrast(DISPLAYCONTRAST);
     oledFill(0, 1);