diff --git a/platform/drivers/display/HX83XX_MDx.c b/platform/drivers/display/HX83XX_MDx.c
index e76b597f..165b0a5e 100644
--- a/platform/drivers/display/HX83XX_MDx.c
+++ b/platform/drivers/display/HX83XX_MDx.c
@@ -88,10 +88,10 @@
 #define LCD_FSMC_ADDR_DATA    0x60040000
 
 /*
- * LCD framebuffer, allocated on the heap by display_init().
+ * LCD framebuffer, statically allocated.
  * Pixel format is RGB565, 16 bit per pixel
  */
-static uint16_t *frameBuffer;
+static uint16_t frameBuffer[SCREEN_WIDTH * SCREEN_HEIGHT];
 
 void __attribute__((used)) DMA2_Stream7_IRQHandler()
 {
@@ -113,19 +113,8 @@ static inline __attribute__((__always_inline__)) void writeData(uint8_t val)
 
 void display_init()
 {
-    /* Framebuffer size, in bytes */
-    const size_t fbSize = SCREEN_WIDTH * SCREEN_HEIGHT * sizeof(uint16_t);
-
-    /* Allocate framebuffer, two bytes per pixel */
-    frameBuffer = (uint16_t *) malloc(fbSize);
-    if(frameBuffer == NULL)
-    {
-        printf("*** LCD ERROR: cannot allocate framebuffer! ***");
-        return;
-    }
-
     /* Clear framebuffer, setting all pixels to 0xFFFF makes the screen white */
-    memset(frameBuffer, 0xFF, fbSize);
+    memset(frameBuffer, 0xFF, SCREEN_WIDTH * SCREEN_HEIGHT * sizeof(uint16_t));
 
     /*
      * Turn on DMA2 and configure its interrupt. DMA is used to transfer the
@@ -335,11 +324,6 @@ void display_terminate()
     /* Shut off FSMC and deallocate framebuffer */
     RCC->AHB3ENR &= ~RCC_AHB3ENR_FSMCEN;
     __DSB();
-
-    if(frameBuffer != NULL)
-    {
-        free(frameBuffer);
-    }
 }
 
 void display_renderRows(uint8_t startRow, uint8_t endRow)
diff --git a/platform/mcu/STM32F4xx/drivers/usb_vcom.c b/platform/mcu/STM32F4xx/drivers/usb_vcom.c
index e2f59d87..43dab47a 100644
--- a/platform/mcu/STM32F4xx/drivers/usb_vcom.c
+++ b/platform/mcu/STM32F4xx/drivers/usb_vcom.c
@@ -39,11 +39,12 @@ static __IO uint32_t usbd_cdc_AltSet = 0;
 uint8_t outEnpBuffer[CDC_DATA_OUT_PACKET_SIZE];
 
 /* Circular buffer for incoming data enqueuement: each packet coming from host
- * is stored here, eventually erasing oldest data
+ * is stored here, eventually erasing oldest data.
+ * Buffer is statically allocated.
  */
 struct rb
 {
-    uint8_t *data;
+    uint8_t data[RX_RING_BUF_SIZE];
     size_t readPtr;
     size_t writePtr;
 }
@@ -203,9 +204,6 @@ int vcom_init()
     rxRingBuf.readPtr = 0;
     rxRingBuf.writePtr = 0;
 
-    rxRingBuf.data = (uint8_t *) malloc(RX_RING_BUF_SIZE);
-    if(rxRingBuf.data == NULL) return -1;
-
     USBD_Init(&USB_OTG_dev, USB_OTG_FS_CORE_ID, &USR_desc, &USBD_CDC_cb,
               &USR_cb);
 
@@ -277,9 +275,6 @@ static uint8_t  usbd_cdc_DeInit (void  *pdev, uint8_t cfgidx)
     /* Open Command IN EP */
     DCD_EP_Close(pdev,CDC_CMD_EP);
 
-    /* Deallocate RX buffer */
-    if(rxRingBuf.data != NULL) free(rxRingBuf.data);
-
     return USBD_OK;
 }