diff --git a/apps/plugins/SOURCES b/apps/plugins/SOURCES
index 95ffb1c..9ee85c9 100644
--- a/apps/plugins/SOURCES
+++ b/apps/plugins/SOURCES
@@ -168,3 +168,4 @@ lua.c
 #if defined(HAVE_USBSTACK) && defined(USB_ENABLE_HID)
 remote_control.c
 #endif
+test_disk.c
diff --git a/apps/plugins/test_disk.c b/apps/plugins/test_disk.c
index 34cb94d..33e04a0 100644
--- a/apps/plugins/test_disk.c
+++ b/apps/plugins/test_disk.c
@@ -24,7 +24,7 @@
 
 PLUGIN_HEADER
 
-#define TESTBASEDIR "/__TEST__"
+#define TESTBASEDIR "/<microSD1>/__TEST__"
 #define TEST_FILE   TESTBASEDIR "/test_disk.tmp"
 #define FRND_SEED   0x78C3     /* arbirary */
 
diff --git a/firmware/target/arm/as3525/ata_sd_as3525.c b/firmware/target/arm/as3525/ata_sd_as3525.c
index 995bf93..756e0a6 100644
--- a/firmware/target/arm/as3525/ata_sd_as3525.c
+++ b/firmware/target/arm/as3525/ata_sd_as3525.c
@@ -104,8 +104,9 @@ static void init_pl180_controller(const int drive);
 static tCardInfo card_info[NUM_DRIVES];
 
 /* maximum timeouts recommanded in the SD Specification v2.00 */
-#define SD_MAX_READ_TIMEOUT     ((AS3525_PCLK_FREQ) / 1000 * 100) /* 100 ms */
-#define SD_MAX_WRITE_TIMEOUT    ((AS3525_PCLK_FREQ) / 1000 * 250) /* 250 ms */
+#define SD_MCICLK_FREQ          (MCI_CLOCK(drive) & MCI_CLOCK_BYPASS)? AS3525_PCLK_FREQ: ((AS3525_PCLK_FREQ) / (2*((MCI_CLOCK(drive) & 0xff) + 1)))
+#define SD_MAX_READ_TIMEOUT     ((SD_MCICLK_FREQ) / 1000 * 100) /* 100 ms */
+#define SD_MAX_WRITE_TIMEOUT    ((SD_MCICLK_FREQ) / 1000 * 250) /* 250 ms */
 
 /* for compatibility */
 static long last_disk_activity = -1;
@@ -245,6 +246,7 @@ static int sd_init_card(const int drive)
     unsigned long response;
     long init_timeout;
     bool sdhc;
+    bool hscard = false;
     unsigned long temp_reg[4];
     int i;
 
@@ -295,6 +297,9 @@ static int sd_init_card(const int drive)
                 &card_info[drive].rca))
         return -6;
 
+    /* Change to pushpull bus mode for higher frequencies  */
+    MCI_POWER(drive) &= ~MCI_POWER_OPEN_DRAIN;
+
     /* send CSD */
     if(!send_cmd(drive, SD_SEND_CSD, card_info[drive].rca,
                  MCI_RESP|MCI_LONG_RESP|MCI_ARG, temp_reg))
@@ -305,22 +310,31 @@ static int sd_init_card(const int drive)
 
     sd_parse_csd(&card_info[drive]);
 
-    if(!send_cmd(drive, SD_SELECT_CARD, card_info[drive].rca, MCI_ARG, NULL))
-        return -9;
-
-    if(!send_cmd(drive, SD_APP_CMD, card_info[drive].rca, MCI_ARG, NULL))
-        return -10;
+    card_info[drive].initialized = 1;
 
-    if(!send_cmd(drive, SD_SET_BUS_WIDTH, card_info[drive].rca | 2, MCI_ARG, NULL))
-        return -11;
+    if(!send_cmd(drive, SD_SELECT_CARD, card_info[drive].rca, MCI_ARG, NULL))
+        return -8;
 
-    if(!send_cmd(drive, SD_SET_BLOCKLEN, card_info[drive].blocksize, MCI_ARG,
-                 NULL))
-        return -12;
+    /*  Check card for HS capable and if so switch to HS  */
+    if(card_info[drive].speed > 125000)
+    {
+        hscard = true;
+        if(!send_cmd(drive, SD_SWITCH_FUNC, 0x80fffff1, MCI_ARG, NULL))
+            return -9;
+    }
 
-    card_info[drive].initialized = 1;
+    if(drive == 0)
+    {
+        /* full speed for controller clock */
+        MCI_CLOCK(drive) |= MCI_CLOCK_BYPASS;
+    }
+    else
+    {
+        /* Drop freq for uSD Card to spec  ( < 50MHz) */
+        /* MCICLK == PCLK/2 for HS,  PCLK/4 for std */
+        MCI_CLOCK(drive) = MCI_CLOCK_ENABLE | (hscard ? 0: 1);
+    }
 
-    MCI_CLOCK(drive) |= MCI_CLOCK_BYPASS; /* full speed for controller clock */
     mci_delay();
 
     /*
@@ -603,7 +617,7 @@ static int sd_select_bank(signed char bank)
             DMA_PERI_SD, DMAC_FLOWCTRL_PERI_MEM_TO_PERI, true, false, 0, DMA_S8,
             NULL);
 
-        MCI_DATA_TIMER(INTERNAL_AS3525) = SD_MAX_WRITE_TIMEOUT;
+        MCI_DATA_TIMER(INTERNAL_AS3525) = ((AS3525_PCLK_FREQ) / 1000 * 250); /*Max Write Timeout 250 ms */
         MCI_DATA_LENGTH(INTERNAL_AS3525) = 512;
         MCI_DATA_CTRL(INTERNAL_AS3525) =  (1<<0) /* enable */   |
                                 (0<<1) /* transfer direction */ |