diff --git a/DSView/pv/dock/dsotriggerdock.cpp b/DSView/pv/dock/dsotriggerdock.cpp
index 0c19f7a9..6ab67113 100644
--- a/DSView/pv/dock/dsotriggerdock.cpp
+++ b/DSView/pv/dock/dsotriggerdock.cpp
@@ -233,7 +233,7 @@ void DsoTriggerDock::pos_changed(int pos)
     ret = _session->get_device()->set_config_byte(
                                             SR_CONF_HORIZ_TRIGGERPOS,pos);
     if (!ret) {        
-        if (_session->get_device()->is_hardware()){
+        if (_session->get_device()->is_hardware() || true){
             QString strMsg(L_S(STR_PAGE_MSG, S_ID(IDS_MSG_CHANGE_HOR_TRI_POS_FAIL), 
                                        "Change horiz trigger position failed!"));
                                 
@@ -379,6 +379,10 @@ void DsoTriggerDock::update_view()
     bool bDisable = _session->get_device()->is_file();
     bool ret;
 
+    if (_session->get_device()->is_demo()){
+        bDisable = true;
+    }
+
     for(QAbstractButton * btn :  _source_group->buttons()){
         btn->setDisabled(bDisable);
     }
@@ -396,6 +400,11 @@ void DsoTriggerDock::update_view()
     _position_spinBox->setDisabled(bDisable);
     _position_slider->setDisabled(bDisable);
 
+    if (_session->get_device()->is_demo()){
+        _position_spinBox->setDisabled(false);
+        _position_slider->setDisabled(false);
+    }
+
     if (_session->get_device()->is_file()){
         return;
     }
diff --git a/libsigrok4DSL/hardware/demo/demo.c b/libsigrok4DSL/hardware/demo/demo.c
index 7efbc9de..15c19a54 100644
--- a/libsigrok4DSL/hardware/demo/demo.c
+++ b/libsigrok4DSL/hardware/demo/demo.c
@@ -884,6 +884,9 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
     case SR_CONF_CHANNEL_MODE:
         *data = g_variant_new_int16(vdev->logic_ch_mode);
         break;
+    case SR_CONF_HORIZ_TRIGGERPOS:
+        *data = g_variant_new_byte(vdev->trigger_hrate);
+        break;
     default:
         return SR_ERR_NA;
     }
@@ -1118,6 +1121,9 @@ static int config_set(int id, GVariant *data, struct sr_dev_inst *sdi,
 
         }
         break;
+     case SR_CONF_HORIZ_TRIGGERPOS:
+        vdev->trigger_hrate = g_variant_get_byte(data);
+        break;
     default:
         sr_err("Unknown capability: %d.", id);
         return SR_ERR_NA;
diff --git a/libsigrok4DSL/hardware/demo/demo.h b/libsigrok4DSL/hardware/demo/demo.h
index 04727bfd..84bf417a 100644
--- a/libsigrok4DSL/hardware/demo/demo.h
+++ b/libsigrok4DSL/hardware/demo/demo.h
@@ -204,6 +204,7 @@ struct session_vdev
     uint8_t max_height;
     struct sr_status mstatus;
     struct session_packet_buffer   *packet_buffer;
+    uint8_t   trigger_hrate; //dso trig position.
 
     //time
     uint64_t packet_len;