diff --git a/extras/ssd1306/ssd1306.c b/extras/ssd1306/ssd1306.c
index dae29fa..b78a6e9 100644
--- a/extras/ssd1306/ssd1306.c
+++ b/extras/ssd1306/ssd1306.c
@@ -128,6 +128,15 @@ int ssd1306_command(const ssd1306_t *dev, uint8_t cmd)
             gpio_write(dev->cs_pin, true);
             break;
 #endif
+#if (SSD1306_SPI3_SUPPORT)
+        case SSD1306_PROTO_SPI3:
+            gpio_write(dev->cs_pin, false);
+            spi_set_command(SPI_BUS,1,0); // command mode
+            spi_transfer_8(SPI_BUS, cmd);
+            spi_clear_command(SPI_BUS);
+            gpio_write(dev->cs_pin, true);
+            break;
+#endif
 #if (SSD1306_SPI3_SUPPORT)
         case SSD1306_PROTO_SPI3:
             gpio_write(dev->cs_pin, false);
diff --git a/extras/ssd1306/ssd1306.h b/extras/ssd1306/ssd1306.h
index cdfae61..9f620d1 100644
--- a/extras/ssd1306/ssd1306.h
+++ b/extras/ssd1306/ssd1306.h
@@ -192,6 +192,14 @@ int ssd1306_set_display_offset(const ssd1306_t *dev, uint8_t offset);
  */
 int sh1106_set_charge_pump_voltage(const ssd1306_t *dev, sh1106_voltage_t select);
 
+/**
+ * Select charge pump voltage. See value in datasheet.
+ * @param dev Pointer to device descriptor
+ * @param select Select charge pump voltage value
+ * @return Non-zero if error occured
+ */
+int sh1106_set_charge_pump_voltage(const ssd1306_t *dev, sh1106_voltage_t select);
+
 /**
  * Enable or disable the charge pump. See application note in datasheet.
  * @param dev Pointer to device descriptor