diff --git a/DSView/pv/ui/langresource.cpp b/DSView/pv/ui/langresource.cpp
index 1c0c1ecf..2dea930b 100644
--- a/DSView/pv/ui/langresource.cpp
+++ b/DSView/pv/ui/langresource.cpp
@@ -32,10 +32,19 @@
 #include <assert.h>
 
 //---------------Lang_resource_page
+Lang_resource_page::Lang_resource_page()
+{
+    _id = -1;
+    _source = NULL;
+    _loaded = false;
+    _released = false;
+    _is_dynamic = false;
+}
 
 void Lang_resource_page::Clear()
 {
     _res.clear();
+    _res_history.clear();
 }
 
 //---------------LangResource
@@ -88,7 +97,9 @@ bool LangResource::Load(int lang)
 
     _cur_lang = lang;
 
-    Release();
+    _query_decoders.clear();
+
+    this->Release();
 
     num = sizeof(lange_page_keys) / sizeof(lang_page_item);
 
@@ -97,7 +108,7 @@ bool LangResource::Load(int lang)
         Lang_resource_page *p = new Lang_resource_page();
         p->_id = lange_page_keys[i].id;
         p->_source = lange_page_keys[i].source;
-        p->_loaded = false;
+        p->_is_dynamic = lange_page_keys[i].is_dynamic;
         _pages.push_back(p);
     }
 
@@ -139,7 +150,7 @@ void LangResource::load_page(Lang_resource_page &p, QString file)
 { 
     QFile f(file);
     if (f.exists() == false){
-        if (_cur_lang != LAN_EN)
+        if (_cur_lang != LAN_EN && p._is_dynamic == false)
             dsv_warn("Warning:Language source file is not exists: %s", file.toLocal8Bit().data());
         return;
     }
@@ -179,7 +190,7 @@ void LangResource::load_page(Lang_resource_page &p, QString file)
 const char* LangResource::get_lang_text(int page_id, const char *str_id, const char *default_str)
 {
     assert(str_id);
-    assert(default_str);
+    assert(default_str); 
 
     if (*str_id == '\0' || *default_str == '\0'){
         dsv_err("%s", "LangResource::get_lang_text(), param is empty.");
@@ -198,20 +209,68 @@ const char* LangResource::get_lang_text(int page_id, const char *str_id, const c
 
     if (_current_page == NULL){
         if (_cur_lang != LAN_EN)
-            dsv_warn("Warning:Cant find language source page:%d", page_id);
+            dsv_warn("Warning:Can't find language source page:%d", page_id);
         return default_str;
     }
 
     if (_current_page->_loaded == false)
         load_page(*_current_page);
 
-    auto it = _current_page->_res.find(std::string(str_id));
-    if (it != _current_page->_res.end()){
-        return (*it).second.c_str();
+    std::string key(str_id);
+
+    if (_current_page->_released){
+        auto it = _current_page->_res_history.find(key);
+        if (it != _current_page->_res_history.end()){
+            return (*it).second.c_str();
+        }
     }
-    else if(_cur_lang != LAN_EN){
-        dsv_warn("Warning:Cant't get language text:%s", str_id);
+    else{
+        auto it = _current_page->_res.find(key);
+        if (it != _current_page->_res.end()){
+            if (_current_page->_is_dynamic){
+                _current_page->_res_history[key] = (*it).second; //Save to history list.
+            }
+            return (*it).second.c_str();
+        }
+    }   
+   
+    if(_cur_lang != LAN_EN){
+        dsv_warn("Warning:Can't get language text:%s", str_id);
     }
 
     return default_str;
 }
+
+bool LangResource::is_new_decoder(const char *decoder_id)
+{
+    std::string key(decoder_id);
+    if (_query_decoders.find(key) == _query_decoders.end()){
+        _query_decoders[key] = 1;
+        return true;
+    }
+
+    return false;
+}
+
+void LangResource::reload_dynamic()
+{
+    for (Lang_resource_page *p : _pages)
+    {
+        if (p->_is_dynamic){
+            p->_released = false;
+            p->_loaded = false;
+            load_page(*p);
+        }
+    }
+}
+
+void LangResource::relase_dynamic()
+{
+    for (Lang_resource_page *p : _pages)
+    {
+        if (p->_is_dynamic){
+            p->_res.clear();
+            p->_released = true;
+        }
+    }
+}
diff --git a/DSView/pv/ui/langresource.h b/DSView/pv/ui/langresource.h
index 0a20aea9..f9e9e989 100644
--- a/DSView/pv/ui/langresource.h
+++ b/DSView/pv/ui/langresource.h
@@ -25,6 +25,7 @@
 #include <map>
 #include <vector>
 #include <QString>
+#include <string>
 #include "string_ids.h"
 
 struct lang_key_item
@@ -36,19 +37,24 @@ struct lang_key_item
 class Lang_resource_page
 {
 public:
+    Lang_resource_page();
     void Clear();
 
 public:
     int     _id;
     const char   *_source;
     bool    _loaded;
+    bool    _released;
+    bool    _is_dynamic;
     std::map<std::string, std::string> _res;
+    std::map<std::string, std::string> _res_history;
 };
 
 struct lang_page_item
 {
     int id;
     const char *source;
+    bool is_dynamic;
 };
 
 static const struct lang_key_item lang_id_keys[] = 
@@ -59,10 +65,11 @@ static const struct lang_key_item lang_id_keys[] =
 
 static const struct lang_page_item lange_page_keys[] = 
 {
-    {STR_PAGE_TOOLBAR, "toolbar.json"},
-    {STR_PAGE_MSG, "msg.json"},
-    {STR_PAGE_DLG, "dlg.json"},
-    {STR_PAGE_DSL, "dsl_list.json, dsl_label.json, dsl_channel.json"}
+    {STR_PAGE_TOOLBAR, "toolbar.json", false},
+    {STR_PAGE_MSG, "msg.json", false},
+    {STR_PAGE_DLG, "dlg.json", false},
+    {STR_PAGE_DSL, "dsl_list.json, dsl_label.json, dsl_channel.json", false},
+    {STR_PAGE_DECODER, "dec/0.json,dec/a.json,dec/f.json,dec/k.json,dec/p.json,dec/u.json", true},
 };
 
 class LangResource
@@ -74,8 +81,12 @@ public:
     static LangResource* Instance();
     bool Load(int lang);
     void Release();
+  
     const char* get_lang_text(int page_id, const char *str_id, const char *default_str);
-
+    bool is_new_decoder(const char *decoder_id);
+    void reload_dynamic();
+    void relase_dynamic();
+   
 private:
     const char *get_lang_key(int lang);
 
@@ -87,6 +98,7 @@ private:
     std::vector<Lang_resource_page*> _pages;
     Lang_resource_page    *_current_page;
     int     _cur_lang;
+    std::map<std::string, int> _query_decoders;
 };
 
 #define S_ID(id) #id
diff --git a/DSView/pv/ui/string_ids.h b/DSView/pv/ui/string_ids.h
index 6e86d157..c6f72bae 100644
--- a/DSView/pv/ui/string_ids.h
+++ b/DSView/pv/ui/string_ids.h
@@ -26,6 +26,7 @@
 #define     STR_PAGE_TOOLBAR    2
 #define     STR_PAGE_DLG        3
 #define     STR_PAGE_DSL        100
+#define     STR_PAGE_DECODER    101
 
 // xx
 #define IDS_TOOLBAR_MODE
diff --git a/lang/en/dsl.json b/lang/en/dsl.json
deleted file mode 100644
index b8e07c0b..00000000
--- a/lang/en/dsl.json
+++ /dev/null
@@ -1,10 +0,0 @@
-[
-    {
-        "id": "vvv",
-        "text": "xxx"
-    },
-    {
-        "id": "vvv1",
-        "text": "xxx1"
-    }
-]
\ No newline at end of file
diff --git a/libsigrok4DSL/session_driver.c b/libsigrok4DSL/session_driver.c
index 770dffc0..572e0671 100644
--- a/libsigrok4DSL/session_driver.c
+++ b/libsigrok4DSL/session_driver.c
@@ -726,7 +726,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
         *data = g_variant_new_int16(vdev->version);
         break;
     default:
-        return SR_ERR_ARG;
+        return SR_ERR_NA;
     }
 
     return SR_OK;
@@ -949,7 +949,7 @@ static int config_set(int id, GVariant *data, struct sr_dev_inst *sdi,
         break;
     default:
         sr_err("Unknown capability: %d.", id);
-        return SR_ERR;
+        return SR_ERR_NA;
     }
 
     return SR_OK;