diff --git a/src/FatFs/ffconf.h b/src/FatFs/ffconf.h
index 636937af1..643b8b980 100644
--- a/src/FatFs/ffconf.h
+++ b/src/FatFs/ffconf.h
@@ -9,15 +9,6 @@
 #ifndef _FFCONF
 #define _FFCONF 6502	/* Revision ID */
 
-#if defined(PCBARM) && !defined(SIMU)
-#ifdef __cplusplus
-extern "C" {
-#endif
-#include "../CoOS/kernel/CoOS.h"
-#ifdef __cplusplus
-}
-#endif
-#endif
 
 /*---------------------------------------------------------------------------/
 / Functions and Buffer Configurations
@@ -98,11 +89,8 @@ extern "C" {
 /	1    - ASCII only (Valid for non LFN cfg.)
 */
 
-#if defined(PCBARM)
-#define	_USE_LFN	2		/* 0 to 3 */
-#else
-#define _USE_LFN        1               /* 0 to 3 */
-#endif
+
+#define	_USE_LFN	1		/* 0 to 3 */
 #define	_MAX_LFN	255		/* Maximum LFN length to handle (12 to 255) */
 /* The _USE_LFN option switches the LFN support.
 /
@@ -182,13 +170,9 @@ extern "C" {
 /* A header file that defines sync object types on the O/S, such as
 /  windows.h, ucos_ii.h and semphr.h, must be included prior to ff.h. */
 
-#if defined(PCBARM)
-#define _FS_REENTRANT		1	   /* 0:Disable or 1:Enable */
-#else
-#define _FS_REENTRANT		0	   /* 0:Disable or 1:Enable */
-#endif
-#define _FS_TIMEOUT		1000	   /* Timeout period in unit of time ticks */
-#define	_SYNC_t			OS_MutexID /* O/S dependent type of sync object. e.g. HANDLE, OS_EVENT*, ID and etc.. */
+#define _FS_REENTRANT	0		/* 0:Disable or 1:Enable */
+#define _FS_TIMEOUT		1000	/* Timeout period in unit of time ticks */
+#define	_SYNC_t			HANDLE	/* O/S dependent type of sync object. e.g. HANDLE, OS_EVENT*, ID and etc.. */
 
 /* The _FS_REENTRANT option switches the reentrancy (thread safe) of the FatFs module.
 /
@@ -197,12 +181,8 @@ extern "C" {
 /      ff_req_grant, ff_rel_grant, ff_del_syncobj and ff_cre_syncobj
 /      function must be added to the project. */
 
-#if defined(PCBARM)
-#define	_FS_SHARE	3	/* 0:Disable or >=1:Enable */
-#else
-#define _FS_SHARE       2       /* 0:Disable or >=1:Enable */
-#endif
 
+#define	_FS_SHARE	0	/* 0:Disable or >=1:Enable */
 /* To enable file shareing feature, set _FS_SHARE to 1 or greater. The value
    defines how many files can be opened simultaneously. */
 
diff --git a/src/ersky9x/diskio.c b/src/ersky9x/diskio.c
index aec3654a9..7cc37adf7 100644
--- a/src/ersky9x/diskio.c
+++ b/src/ersky9x/diskio.c
@@ -89,31 +89,6 @@ uint8_t  cardType;
 const uint8_t SpeedTable[] = { 1, 10, 12, 13, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 70, 80 } ;
 uint32_t sdSpeedAllowed ;
 
-/*-----------------------------------------------------------------------*/
-/* Lock / unlock functions                                               */
-/*-----------------------------------------------------------------------*/
-int ff_cre_syncobj (BYTE vol, _SYNC_t *mutex)
-{
-  *mutex = CoCreateMutex();
-  return 1;
-}
-
-int ff_req_grant (_SYNC_t mutex)
-{
-  CoEnterMutexSection(mutex);
-  return 1;
-}
-
-void ff_rel_grant (_SYNC_t mutex)
-{
-  CoLeaveMutexSection(mutex);
-}
-
-int ff_del_syncobj (_SYNC_t mutex)
-{
-  return 1;
-}
-
 /**
  * Configure the  MCI CLKDIV in the MCI_MR register. The max. for MCI clock is
  * MCK/2 and corresponds to CLKDIV = 0
@@ -1015,12 +990,16 @@ uint32_t sd_cmd16()
 #endif
 }
 
+extern OS_MutexID sdMutex;
+
 uint32_t sd_read_block(uint32_t block_no, uint32_t *data)
 {
   uint32_t result = 0;
   Hsmci *phsmci = HSMCI;
   int32_t retry;
 
+  CoEnterMutexSection(sdMutex);
+
   if (sd_card_ready()) {
       sd_cmd16();
       // Block size = 512, nblocks = 1
@@ -1046,6 +1025,7 @@ uint32_t sd_read_block(uint32_t block_no, uint32_t *data)
   /* Disable PDC */
   phsmci->HSMCI_PTCR = HSMCI_PTCR_RXTDIS | HSMCI_PTCR_TXTDIS;
 
+  CoLeaveMutexSection(sdMutex);
   return result;
 }
 
@@ -1055,6 +1035,8 @@ uint32_t sd_write_block( uint32_t block_no, uint32_t *data )
   Hsmci *phsmci = HSMCI;
   int32_t retry;
 
+  CoEnterMutexSection(sdMutex);
+
   if (sd_card_ready()) {
 
     // TRACE_ERROR("Sector %d ", block_no);
@@ -1076,10 +1058,9 @@ uint32_t sd_write_block( uint32_t block_no, uint32_t *data )
       phsmci->HSMCI_ARGR = (Cmd_A41_resp & OCR_SD_CCS ? block_no : (block_no << 9));
       phsmci->HSMCI_TPR  = (uint32_t)data;
       phsmci->HSMCI_TCR  = 512 / 4;
-      phsmci->HSMCI_TNCR = 0;
       phsmci->HSMCI_CMDR = SD_WRITE_SINGLE_BLOCK;
       phsmci->HSMCI_PTCR = HSMCI_PTCR_TXTEN;
-
+      
       retry = 500;
       while (--retry >= 0) {
         CoTickDelay(1); // 2ms
@@ -1106,6 +1087,8 @@ uint32_t sd_write_block( uint32_t block_no, uint32_t *data )
 
   phsmci->HSMCI_MR &= ~(uint32_t)HSMCI_MR_PDCMODE;
 
+  CoLeaveMutexSection(sdMutex);
+
   return result;
 }