diff --git a/src/disk/hdd_image.c b/src/disk/hdd_image.c
index eff860804..bccf13374 100644
--- a/src/disk/hdd_image.c
+++ b/src/disk/hdd_image.c
@@ -499,20 +499,16 @@ hdd_image_read(uint8_t id, uint32_t sector, uint32_t count, uint8_t *buffer)
 		int non_transferred_sectors = mvhd_read_sectors(hdd_images[id].vhd, sector, count, buffer);
 		hdd_images[id].pos = sector + count - non_transferred_sectors - 1;
 	} else {
-		int i;
-
 		if (fseeko64(hdd_images[id].file, ((uint64_t)(sector) << 9LL) + hdd_images[id].base, SEEK_SET) == -1) {
 			fatal("Hard disk image %i: Read error during seek\n", id);
 			return;
 		}
 
-		for (i = 0; i < count; i++) {
-			if (feof(hdd_images[id].file))
-				break;
-
-			hdd_images[id].pos = sector + i;
-			fread(buffer + (i << 9), 1, 512, hdd_images[id].file);
+		size_t num_read = fread(buffer, 512, count, hdd_images[id].file);
+		if (num_read != count) {
+			fatal("Hard disk image %i: Read error\n", id);
 		}
+		hdd_images[id].pos = sector + num_read;
 	}
 }
 
@@ -555,20 +551,16 @@ hdd_image_write(uint8_t id, uint32_t sector, uint32_t count, uint8_t *buffer)
 		int non_transferred_sectors = mvhd_write_sectors(hdd_images[id].vhd, sector, count, buffer);
 		hdd_images[id].pos = sector + count - non_transferred_sectors - 1;
 	} else {
-		int i;
-
 		if (fseeko64(hdd_images[id].file, ((uint64_t)(sector) << 9LL) + hdd_images[id].base, SEEK_SET) == -1) {
 			fatal("Hard disk image %i: Write error during seek\n", id);
 			return;
 		}
 
-		for (i = 0; i < count; i++) {
-			if (feof(hdd_images[id].file))
-				break;
-
-			hdd_images[id].pos = sector + i;
-			fwrite(buffer + (i << 9), 512, 1, hdd_images[id].file);
+		size_t num_write = fwrite(buffer, 512, count, hdd_images[id].file);
+		if (num_write != count) {
+			fatal("Hard disk image %i: Write error\n", id);
 		}
+		hdd_images[id].pos = sector + num_write;
 	}
 }
 
diff --git a/src/port_6x.c b/src/port_6x.c
index dafa5d987..62b1558fb 100644
--- a/src/port_6x.c
+++ b/src/port_6x.c
@@ -71,70 +71,75 @@ port_6x_write(uint16_t port, uint8_t val, void *priv)
     }
 }
 
-
 static uint8_t
-port_6x_read(uint16_t port, void *priv)
+port_61_read_simple(uint16_t port, void *priv)
 {
-    port_6x_t *dev = (port_6x_t *) priv;
-    uint8_t ret = 0xff;
+    uint8_t ret = ppi.pb & 0x1f;
 
-    port &= 3;
-
-    if ((port == 3) && (dev->flags & PORT_6X_MIRROR))
-	port = 1;
-
-    switch (port) {
-	case 1:
-		if (dev->flags & PORT_6X_EXT_REF) {
-		    	ret = ppi.pb & 0x0f;
-
-			if (dev->refresh)
-				ret |= 0x10;
-		} else
-			ret = ppi.pb & 0x1f;
-
-		if (ppispeakon)
-			ret |= 0x20;
-
-		if (dev->flags & PORT_6X_TURBO)
-			ret = (ret & 0xfb) | (xi8088_turbo_get() ? 0x04 : 0x00);
-		break;
-	case 2:
-		if (dev->flags & PORT_6X_SWA) {
-			/* SWA on Olivetti M240 mainboard (off=1) */
-			ret = 0x00;
-			if (ppi.pb & 0x8) {
-				/* Switches 4, 5 - floppy drives (number) */
-				int i, fdd_count = 0;
-				for (i = 0; i < FDD_NUM; i++) {
-				    if (fdd_get_flags(i))
-				        fdd_count++;
-				}
-				if (!fdd_count)
-					ret |= 0x00;
-				else
-					ret |= ((fdd_count - 1) << 2);
-				/* Switches 6, 7 - monitor type */
-				if (video_is_mda())
-					ret |= 0x3;
-				else if (video_is_cga())
-					ret |= 0x2;	/* 0x10 would be 40x25 */
-				else
-					ret |= 0x0;
-			} else {
-				/* bit 2 always on */
-				ret |= 0x4;
-				/* Switch 8 - 8087 FPU. */
-				if (hasfpu)
-					ret |= 0x02;
-			}
-		}
-		break;
-    }
+    if (ppispeakon)
+        ret |= 0x20;
 
     return(ret);
 }
 
+static uint8_t
+port_61_read(uint16_t port, void *priv)
+{
+    port_6x_t *dev = (port_6x_t *) priv;
+    uint8_t ret = 0xff;
+
+    if (dev->flags & PORT_6X_EXT_REF) {
+        ret = ppi.pb & 0x0f;
+
+        if (dev->refresh)
+            ret |= 0x10;
+    } else
+        ret = ppi.pb & 0x1f;
+
+    if (ppispeakon)
+        ret |= 0x20;
+
+    if (dev->flags & PORT_6X_TURBO)
+        ret = (ret & 0xfb) | (xi8088_turbo_get() ? 0x04 : 0x00);
+
+    return(ret);
+}
+
+static uint8_t
+port_62_read(uint16_t port, void *priv)
+{
+    uint8_t ret = 0xff;
+
+    /* SWA on Olivetti M240 mainboard (off=1) */
+    ret = 0x00;
+    if (ppi.pb & 0x8) {
+        /* Switches 4, 5 - floppy drives (number) */
+        int i, fdd_count = 0;
+        for (i = 0; i < FDD_NUM; i++) {
+            if (fdd_get_flags(i))
+                fdd_count++;
+        }
+        if (!fdd_count)
+            ret |= 0x00;
+        else
+            ret |= ((fdd_count - 1) << 2);
+        /* Switches 6, 7 - monitor type */
+        if (video_is_mda())
+            ret |= 0x3;
+        else if (video_is_cga())
+            ret |= 0x2; /* 0x10 would be 40x25 */
+        else
+            ret |= 0x0;
+    } else {
+        /* bit 2 always on */
+        ret |= 0x4;
+        /* Switch 8 - 8087 FPU. */
+        if (hasfpu)
+            ret |= 0x02;
+    }
+
+    return(ret);
+}
 
 static void
 port_6x_refresh(void *priv)
@@ -165,10 +170,19 @@ port_6x_init(const device_t *info)
 
     dev->flags = info->local & 0xff;
 
-    io_sethandler(0x0061, 3, port_6x_read, NULL, NULL, port_6x_write, NULL, NULL, dev);
+    if (!(dev->flags & PORT_6X_TURBO) || (dev->flags & PORT_6X_EXT_REF))
+        io_sethandler(0x0061, 1, port_61_read_simple, NULL, NULL, port_6x_write, NULL, NULL, dev);
+    else
+        io_sethandler(0x0061, 1, port_61_read, NULL, NULL, port_6x_write, NULL, NULL, dev);
+
+    if (dev->flags & PORT_6X_SWA)
+        io_sethandler(0x0062, 1, port_62_read, NULL, NULL, NULL, NULL, NULL, dev);
+
+    if (dev->flags & PORT_6X_MIRROR)
+        io_sethandler(0x0063, 1, port_61_read, NULL, NULL, port_6x_write, NULL, NULL, dev);
 
     if (dev->flags & PORT_6X_EXT_REF)
-	timer_add(&dev->refresh_timer, port_6x_refresh, dev, 1);
+	   timer_add(&dev->refresh_timer, port_6x_refresh, dev, 1);
 
     return dev;
 }
diff --git a/src/qt/sdl_joystick.cpp b/src/qt/sdl_joystick.cpp
index 0e7bfd619..ab72145c3 100644
--- a/src/qt/sdl_joystick.cpp
+++ b/src/qt/sdl_joystick.cpp
@@ -107,6 +107,8 @@ void joystick_process()
 {
     int c, d;
 
+    if (!joystick_type) return;
+
     SDL_JoystickUpdate();
     for (c = 0; c < joysticks_present; c++)
     {