diff --git a/stm32h743_usbhs_msc/Core/Src/usb_msc_dual_sdmmc.c b/stm32h743_usbhs_msc/Core/Src/usb_msc_dual_sdmmc.c
index d211878..95b1196 100644
--- a/stm32h743_usbhs_msc/Core/Src/usb_msc_dual_sdmmc.c
+++ b/stm32h743_usbhs_msc/Core/Src/usb_msc_dual_sdmmc.c
@@ -188,8 +188,14 @@ int usbd_msc_sector_read(uint8_t busid, uint8_t lun, uint32_t sector, uint8_t *b
 
     while(HAL_MMC_GetCardState(&hmmc1) != HAL_MMC_CARD_TRANSFER);
 
-    HAL_MMC_ReadBlocks_DMA(&hmmc1, buffer, sector, length / 512);
-    xSemaphoreTake(mmc1_rx_semphr, portMAX_DELAY);
+    if (HAL_MMC_ReadBlocks_DMA(&hmmc1, buffer, sector, length / MMC_BLOCKSIZE) != HAL_OK) {
+      USB_LOG_ERR("error while issuing dma read command to emmc1");
+      return 1;
+    }
+    if (xSemaphoreTake(mmc1_rx_semphr, pdMS_TO_TICKS(500)) != pdTRUE) {
+      USB_LOG_ERR("timeout while taking dma read semaphore of emmc1");
+      return 1;
+    }
 
     HAL_GPIO_WritePin(LED_Y1_GPIO_Port, LED_Y1_Pin, GPIO_PIN_RESET);
   }
@@ -198,8 +204,14 @@ int usbd_msc_sector_read(uint8_t busid, uint8_t lun, uint32_t sector, uint8_t *b
 
     while(HAL_MMC_GetCardState(&hmmc2) != HAL_MMC_CARD_TRANSFER);
 
-    HAL_MMC_ReadBlocks_DMA(&hmmc2, buffer, sector, length / 512);
-    xSemaphoreTake(mmc2_rx_semphr, portMAX_DELAY);
+    if (HAL_MMC_ReadBlocks_DMA(&hmmc2, buffer, sector, length / MMC_BLOCKSIZE) != HAL_OK) {
+      USB_LOG_ERR("error while issuing dma read command to emmc2");
+      return 1;
+    }
+    if (xSemaphoreTake(mmc2_rx_semphr, pdMS_TO_TICKS(500)) != pdTRUE) {
+      USB_LOG_ERR("timeout while taking dma read semaphore of emmc2");
+      return 1;
+    }
 
     HAL_GPIO_WritePin(LED_Y2_GPIO_Port, LED_Y2_Pin, GPIO_PIN_RESET);
   } else {
@@ -220,8 +232,14 @@ int usbd_msc_sector_write(uint8_t busid, uint8_t lun, uint32_t sector, uint8_t *
 
     while(HAL_MMC_GetCardState(&hmmc1) != HAL_MMC_CARD_TRANSFER);
 
-    HAL_MMC_WriteBlocks_DMA(&hmmc1, buffer, sector, length / 512);
-    xSemaphoreTake(mmc1_tx_semphr, portMAX_DELAY);
+    if (HAL_MMC_WriteBlocks_DMA(&hmmc1, buffer, sector, length / MMC_BLOCKSIZE) != HAL_OK) {
+      USB_LOG_ERR("error while issuing dma write command to emmc1");
+      return 1;
+    }
+    if (xSemaphoreTake(mmc1_tx_semphr, pdMS_TO_TICKS(500)) != pdTRUE) {
+      USB_LOG_ERR("timeout while taking dma write semaphore of emmc1");
+      return 1;
+    }
 
     HAL_GPIO_WritePin(LED_Y1_GPIO_Port, LED_Y1_Pin, GPIO_PIN_RESET);
   } else if (lun == 1) {
@@ -229,8 +247,14 @@ int usbd_msc_sector_write(uint8_t busid, uint8_t lun, uint32_t sector, uint8_t *
 
     while(HAL_MMC_GetCardState(&hmmc2) != HAL_MMC_CARD_TRANSFER);
 
-    HAL_MMC_WriteBlocks_DMA(&hmmc2, buffer, sector, length / 512);
-    xSemaphoreTake(mmc2_tx_semphr, portMAX_DELAY);
+    if (HAL_MMC_WriteBlocks_DMA(&hmmc2, buffer, sector, length / MMC_BLOCKSIZE) != HAL_OK) {
+      USB_LOG_ERR("error while issuing dma write command to emmc2");
+      return 1;
+    }
+    if (xSemaphoreTake(mmc2_tx_semphr, pdMS_TO_TICKS(500)) != pdTRUE) {
+      USB_LOG_ERR("timeout while taking dma write semaphore of emmc2");
+      return 1;
+    }
 
     HAL_GPIO_WritePin(LED_Y2_GPIO_Port, LED_Y2_Pin, GPIO_PIN_RESET);
   } else {