diff --git a/radio/src/disk_cache.cpp b/radio/src/disk_cache.cpp
index b6a6ce79b..df63e5d1e 100644
--- a/radio/src/disk_cache.cpp
+++ b/radio/src/disk_cache.cpp
@@ -24,9 +24,6 @@
 #if defined(SIMU) && !defined(SIMU_DISKIO)
   #define __disk_read(...)    (RES_OK)
   #define __disk_write(...)   (RES_OK)
-#else
-  extern DRESULT __disk_read (BYTE pdrv, BYTE* buff, DWORD sector, UINT count);
-  extern DRESULT __disk_write (BYTE pdrv, const BYTE* buff, DWORD sector, UINT count);
 #endif
 
 #if 0     // set to 1 to enable traces
@@ -37,8 +34,8 @@
 
 DiskCache diskCache;
 
-DiskCacheBlock::DiskCacheBlock() 
-  : startSector(0), 
+DiskCacheBlock::DiskCacheBlock():
+  startSector(0),
   endSector(0) 
 {
 }
@@ -79,8 +76,8 @@ bool DiskCacheBlock::empty() const
   return (endSector == 0);
 }
 
-DiskCache::DiskCache() 
-  : lastBlock(0) 
+DiskCache::DiskCache():
+  lastBlock(0)
 {
   stats.noHits = 0;
   stats.noMisses = 0;
@@ -102,7 +99,7 @@ DRESULT DiskCache::read(BYTE drv, BYTE * buff, DWORD sector, UINT count)
   }
   
   // if block + cache block size is beyond the end of the disk, then read it directly without using cache
-  if (sector+DISK_CACHE_BLOCK_SECTORS >= SDCardInfo.CardCapacity / SDCardInfo.CardBlockSize) {
+  if (sector+DISK_CACHE_BLOCK_SECTORS >= sdGetNoSectors()) {
     TRACE_DISK_CACHE("\t\t cache would be beyond end of disk(%u)", this, (uint32_t)sector);
     return __disk_read(drv, buff, sector, count);
   }
diff --git a/radio/src/lua/CMakeLists.txt b/radio/src/lua/CMakeLists.txt
index d0377914c..5ffe1222e 100644
--- a/radio/src/lua/CMakeLists.txt
+++ b/radio/src/lua/CMakeLists.txt
@@ -13,4 +13,4 @@ endmacro(add_lua_export_target)
 
 add_lua_export_target(taranis     -DCPUARM -DPCBTARANIS          -DLUA -DVIRTUALINPUTS)
 add_lua_export_target(taranis_x9e -DCPUARM -DPCBTARANIS -DPCBX9E -DLUA -DVIRTUALINPUTS)
-add_lua_export_target(horus       -DCPUARM -DPCBHORUS            -DLUA -DVIRTUALINPUTS -I${RADIO_SRC_DIRECTORY}/gui/horus)
+add_lua_export_target(horus       -DCPUARM -DPCBHORUS            -DLUA -DVIRTUALINPUTS -I${RADIO_SRC_DIRECTORY}/gui/480x272)
diff --git a/radio/src/sdcard.cpp b/radio/src/sdcard.cpp
index 714275f56..bbc560816 100644
--- a/radio/src/sdcard.cpp
+++ b/radio/src/sdcard.cpp
@@ -326,7 +326,7 @@ uint32_t sdGetNoSectors()
 
 uint32_t sdGetSize()
 {
-  return (sdGetNoSectors() * 512) / 1000000;
+  return (sdGetNoSectors() * BLOCK_SIZE) / 1000000;
 }
 
 uint32_t sdGetFreeSectors()
diff --git a/radio/src/targets/common/arm/stm32/usbd_storage_msd.cpp b/radio/src/targets/common/arm/stm32/usbd_storage_msd.cpp
index f8caf438c..61c672727 100644
--- a/radio/src/targets/common/arm/stm32/usbd_storage_msd.cpp
+++ b/radio/src/targets/common/arm/stm32/usbd_storage_msd.cpp
@@ -229,7 +229,8 @@ int8_t STORAGE_Read (uint8_t lun,
   }
 #endif
   
-  return (disk_read(0, buf, blk_addr, blk_len) == RES_OK) ? 0 : -1;
+  // read without cache
+  return (__disk_read(0, buf, blk_addr, blk_len) == RES_OK) ? 0 : -1;
 }
 /**
   * @brief  Write data to the medium
@@ -250,8 +251,9 @@ int8_t STORAGE_Write (uint8_t lun,
     return (fat12Write(buf, blk_addr, blk_len) == 0) ? 0 : -1;
   }
 #endif
-
-  return (disk_write(0, buf, blk_addr, blk_len) == RES_OK) ? 0 : -1;
+  
+  // write without cache
+  return (__disk_write(0, buf, blk_addr, blk_len) == RES_OK) ? 0 : -1;
 }
 
 /**
diff --git a/radio/src/targets/horus/board.h b/radio/src/targets/horus/board.h
index a44dd4264..0d1169afb 100644
--- a/radio/src/targets/horus/board.h
+++ b/radio/src/targets/horus/board.h
@@ -100,24 +100,33 @@ void delay_ms(uint32_t ms);
 void getCPUUniqueID(char * s);
 
 // SD driver
+#define BLOCK_SIZE                     512 /* Block Size in Bytes */
 #if !defined(SIMU) || defined(SIMU_DISKIO)
-  uint32_t sdIsHC(void);
-  uint32_t sdGetSpeed(void);
-  #define SD_IS_HC()                   (sdIsHC())
-  #define SD_GET_SPEED()               (sdGetSpeed())
-  #define SD_GET_FREE_BLOCKNR()        (sdGetFreeSectors())
-  #define SD_CARD_PRESENT()            (~SD_PRESENT_GPIO->IDR & SD_PRESENT_GPIO_PIN)
-  void sdInit(void);
-  void sdDone(void);
-  #define sdPoll10ms()
-  #define sdMountPoll()
-  uint32_t sdMounted(void);
+uint32_t sdIsHC(void);
+uint32_t sdGetSpeed(void);
+#define SD_IS_HC()                     (sdIsHC())
+#define SD_GET_SPEED()                 (sdGetSpeed())
+#define SD_GET_FREE_BLOCKNR()          (sdGetFreeSectors())
+#define SD_CARD_PRESENT()              (~SD_PRESENT_GPIO->IDR & SD_PRESENT_GPIO_PIN)
+void sdInit(void);
+void sdDone(void);
+#define sdPoll10ms()
+#define sdMountPoll()
+uint32_t sdMounted(void);
 #else
-  #define SD_IS_HC()                   (0)
-  #define SD_GET_SPEED()               (0)
-  #define sdInit()
-  #define sdDone()
-  #define SD_CARD_PRESENT()            true
+#define SD_IS_HC()                     (0)
+#define SD_GET_SPEED()                 (0)
+#define sdInit()
+#define sdDone()
+#define SD_CARD_PRESENT()              true
+#endif
+#if defined(DISK_CACHE)
+#include "diskio.h"
+DRESULT __disk_read(BYTE drv, BYTE * buff, DWORD sector, UINT count);
+DRESULT __disk_write(BYTE drv, const BYTE * buff, DWORD sector, UINT count);
+#else
+#define __disk_read                    disk_read
+#define __disk_write                   disk_write
 #endif
 
 // Flash Write driver
diff --git a/radio/src/targets/horus/diskio.cpp b/radio/src/targets/horus/diskio.cpp
index dfd4bf198..d261f1faf 100644
--- a/radio/src/targets/horus/diskio.cpp
+++ b/radio/src/targets/horus/diskio.cpp
@@ -110,15 +110,10 @@ uint32_t sdReadRetries = 0;
 /*-----------------------------------------------------------------------*/
 /* Read Sector(s)                                                        */
 
-#if !defined(DISK_CACHE)
-  #define __disk_read     disk_read
-  #define __disk_write    disk_write
-#endif
-
-DRESULT __disk_read (
+DRESULT __disk_read(
   BYTE drv,               /* Physical drive nmuber (0..) */
-  BYTE *buff,             /* Data buffer to store read data */
-  DWORD sector,   				/* Sector address (LBA) */
+  BYTE * buff,            /* Data buffer to store read data */
+  DWORD sector,   	  /* Sector address (LBA) */
   UINT count              /* Number of sectors to read (1..255) */
 )
 {
@@ -194,10 +189,10 @@ DRESULT __disk_read (
 /* Write Sector(s)                                                       */
 
 #if _READONLY == 0
-DRESULT __disk_write (
+DRESULT __disk_write(
   BYTE drv,                       /* Physical drive nmuber (0..) */
-  const BYTE *buff,       /* Data to be written */
-  DWORD sector,           /* Sector address (LBA) */
+  const BYTE *buff,               /* Data to be written */
+  DWORD sector,                   /* Sector address (LBA) */
   UINT count                      /* Number of sectors to write (1..255) */
 )
 {
@@ -250,9 +245,6 @@ DRESULT __disk_write (
 }
 #endif /* _READONLY */
 
-
-
-
 /*-----------------------------------------------------------------------*/
 /* Miscellaneous Functions                                               */
 
diff --git a/radio/src/targets/horus/sdio_sd.h b/radio/src/targets/horus/sdio_sd.h
index 122be50fc..b075ee14f 100644
--- a/radio/src/targets/horus/sdio_sd.h
+++ b/radio/src/targets/horus/sdio_sd.h
@@ -24,8 +24,6 @@
 
 #include "board.h"
 
-#define BLOCK_SIZE            512 /* Block Size in Bytes */
-
 #ifdef __cplusplus
  extern "C" {
 #endif
diff --git a/radio/src/targets/simu/simpgmspace.cpp b/radio/src/targets/simu/simpgmspace.cpp
index 423b85200..1129a5c27 100644
--- a/radio/src/targets/simu/simpgmspace.cpp
+++ b/radio/src/targets/simu/simpgmspace.cpp
@@ -1105,11 +1105,6 @@ DSTATUS disk_status (BYTE pdrv)
   return (DSTATUS)0;
 }
 
-#if !defined(DISK_CACHE)
-  #define __disk_read     disk_read
-  #define __disk_write    disk_write
-#endif
-
 DRESULT __disk_read (BYTE pdrv, BYTE* buff, DWORD sector, UINT count)
 {
   if (diskImage == 0) return RES_NOTRDY;
diff --git a/radio/src/targets/taranis/board.h b/radio/src/targets/taranis/board.h
index 45d1b65d8..36f8d28f8 100644
--- a/radio/src/targets/taranis/board.h
+++ b/radio/src/targets/taranis/board.h
@@ -159,26 +159,27 @@ void getCPUUniqueID(char * s);
 // SD driver
 #define BLOCK_SIZE                     512 /* Block Size in Bytes */
 #if !defined(SIMU) || defined(SIMU_DISKIO)
-  uint32_t sdIsHC(void);
-  uint32_t sdGetSpeed(void);
-  #define SD_IS_HC()                   (sdIsHC())
-  #define SD_GET_SPEED()               (sdGetSpeed())
-  #define SD_GET_FREE_BLOCKNR()        (sdGetFreeSectors())
+uint32_t sdIsHC(void);
+uint32_t sdGetSpeed(void);
+#define SD_IS_HC()                     (sdIsHC())
+#define SD_GET_SPEED()                 (sdGetSpeed())
+#define SD_GET_FREE_BLOCKNR()          (sdGetFreeSectors())
 #else
-  #define SD_IS_HC()                   (0)
-  #define SD_GET_SPEED()               (0)
+#define SD_IS_HC()                     (0)
+#define SD_GET_SPEED()                 (0)
 #endif
-
+#define __disk_read                    disk_read
+#define __disk_write                   disk_write
 #if defined(SIMU)
-  #define sdInit()
-  #define sdDone()
+#define sdInit()
+#define sdDone()
 #else
-  void sdInit(void);
-  void sdDone(void);
-  void sdPoll10ms(void);
-  #define sdMountPoll()
-  uint32_t sdMounted(void);
-  #define SD_CARD_PRESENT()            (~SD_GPIO_PRESENT->IDR & SD_GPIO_PIN_PRESENT)
+void sdInit(void);
+void sdDone(void);
+void sdPoll10ms(void);
+#define sdMountPoll()
+uint32_t sdMounted(void);
+#define SD_CARD_PRESENT()              (~SD_GPIO_PRESENT->IDR & SD_GPIO_PIN_PRESENT)
 #endif
 
 // Flash Write driver