diff --git a/README.md b/README.md
index 54cf2e6..6d14c70 100644
--- a/README.md
+++ b/README.md
@@ -19,6 +19,12 @@ enthusiast.
 
 This repository contains source of tinySA firmware.
 
+# Support
+
+General tinySA support questions should be posted here: https://groups.io/g/tinysa/messages
+
+Use github issue list only for firmware bugs and preferrably cross post to: https://groups.io/g/tinysa/messages
+
 ## Prepare ARM Cross Tools
 
 **UPDATE**: Recent gcc version works to build tinySA, no need old version.
@@ -54,6 +60,10 @@ Just make in the directory.
 
     $ make
 
+For tinySA Ultra use this command
+
+    $ make TARGET="F303"
+
 ### Build firmware using docker
 
 Using [this docker image](https://hub.docker.com/r/edy555/arm-embedded) and without installing arm toolchain, you can build the firmware.
diff --git a/main.c b/main.c
index c9c6118..e5873df 100644
--- a/main.c
+++ b/main.c
@@ -857,7 +857,7 @@ VNA_SHELL_FUNCTION(cmd_capture)
 static FRESULT cmd_sd_card_mount(void){
   const FRESULT res = f_mount(fs_volume, "", 1);
   if (res != FR_OK)
-    shell_printf("err %d: no card\r\n",res);
+    shell_printf("err: (%d) no card\r\n",res);
   return res;
 }
 
@@ -885,49 +885,43 @@ VNA_SHELL_FUNCTION(cmd_sd_list)
     res = f_findnext(&dj, &fno);
   }
   if (res != FR_OK)
-    shell_printf("err %d\r\n",res);
+    shell_printf("err: (%d)\r\n",res);
   f_closedir(&dj);
 }
 
 VNA_SHELL_FUNCTION(cmd_sd_read)
 {
-  DIR dj;
-  FILINFO fno;
+//  DIR dj;
+//  FILINFO fno;
   FRESULT res;
   char *buf = (char *)spi_buffer;
   if (argc != 1 || argv[0][0] == '?')
   {
-     usage_printf("sd_read {filename}\r\n");
+     usage_printf("usage: sd_read {filename}\r\n");
      return;
   }
   const char *filename = argv[0];
   if (cmd_sd_card_mount() != FR_OK)
     return;
 
-  res = f_findfirst(&dj, &fno, "", filename);
-  if (res != FR_OK || fno.fname[0] == 0)
-    goto error;
+ // res = f_findfirst(&dj, &fno, "", filename);
+ // if (res != FR_OK || fno.fname[0] == 0)
+ //   goto error;
 
-
-  if (f_open(fs_file, fno.fname, FA_OPEN_EXISTING | FA_READ) != FR_OK){
-error:
-    shell_printf("err %d: no file\r\n",res);
+  if ((res = f_open(fs_file, filename, FA_OPEN_EXISTING | FA_READ)) != FR_OK){
+//error:
+    shell_printf("err: (%d) no file\r\n", res);
     return;
   }
-  // shell_printf("sd_read: %s\r\n", filename);
   // number of bytes to follow (file size)
   uint32_t filesize = f_size(fs_file);
-#if 1
-  shell_printf("%u\r\n", filesize);
-#else
   streamWrite(shell_stream, (void *)&filesize, 4);
-#endif
   UINT size = 0;
   // file data (send all data from file)
   while ((res=f_read(fs_file, buf, 512, &size)) == FR_OK && size > 0)
     streamWrite(shell_stream, (void *)buf, size);
-  if (res != FR_OK)
-    goto error;
+//  if (res != FR_OK)
+//    goto error;
   f_close(fs_file);
   return;
 }
diff --git a/nanovna.h b/nanovna.h
index d50b145..c603e78 100644
--- a/nanovna.h
+++ b/nanovna.h
@@ -1384,7 +1384,7 @@ typedef struct properties {
 
 //sizeof(properties_t) == 0x1200
 
-#define CONFIG_MAGIC 0x434f4e5D /* 'CONF' */
+#define CONFIG_MAGIC 0x434f4e5F /* 'CONF' */
 
 extern int16_t lastsaveid;
 //extern properties_t *active_props;