diff --git a/python/biopro/devlib/data.py b/python/biopro/devlib/data.py
index 56a87b9..49e9f01 100644
--- a/python/biopro/devlib/data.py
+++ b/python/biopro/devlib/data.py
@@ -1586,12 +1586,7 @@ class EISZeroOneDataDecoder(RecDataDecoder):
                     else:
                         impedance = 0
 
-                    if (real > 0):
-                        raw_phase = math.atan(img / real) * 180 / math.pi
-                    elif (real == 0):
-                        raw_phase = 90
-                    else:
-                        raw_phase = math.atan(img / real) * 180 / math.pi + 180
+                    raw_phase = math.atan2(img , real) * 180 / math.pi
 
                     if (freq >= 1000000): # 10000 Hz
                         fre_idx = 0
@@ -1602,16 +1597,21 @@ class EISZeroOneDataDecoder(RecDataDecoder):
                     elif (freq >= 1): # 0.01 Hz
                         fre_idx = 3
                     
-                    ideal_raw_phase = phase_coeff[fre_idx][gain] /1e10 * freq + phase_offset[fre_idx][gain] / 1e6
-
+                    ideal_raw_phase = phase_coeff[gain][fre_idx] /1e10 * freq + phase_offset[gain][fre_idx] / 1e6
                     phase = raw_phase - ideal_raw_phase
+                    phase = phase % 180 if phase % 180<=90 else phase % 180-180
 
-                    if (self._first_phase_flag):
-                        self._last_phase = phase
-                        self._first_phase_flag = 0
-                    elif (abs(phase - self._last_phase) >= 90):
-                        phase -= 360
-                        self._last_phase = phase
+                    # last_phase_to90 = self._last_phase % 180 if self._last_phase % 180<=90 else self._last_phase % 180-180
+                    # diff = phase - last_phase_to90
+
+                    # if (self._first_phase_flag):
+                    #     # self._last_phase = phase
+                    #     self._first_phase_flag = 0
+                    # elif (abs(diff) >= 90):
+                    #     phase = self._last_phase + diff + (180 if diff<0 else-180)
+                    # else:
+                    #     phase = self._last_phase + diff
+                    # self._last_phase = phase
 
                     imag_after_cal = impedance * math.sin(round(phase) * math.pi / 180)
                     real_after_cal = impedance * math.cos(round(phase) * math.pi / 180)
diff --git a/python/res/devlib/json/Elite_EIS_1.0.devlib.json b/python/res/devlib/json/Elite_EIS_1.0.devlib.json
index 36c7fb3..7c7fabc 100644
--- a/python/res/devlib/json/Elite_EIS_1.0.devlib.json
+++ b/python/res/devlib/json/Elite_EIS_1.0.devlib.json
@@ -70,7 +70,7 @@
       "description": "DPV current recording period start",
       "record_meta": true,
       "initial": [
-        13422819,
+        13333333,
         7
       ],
       "domain": {
diff --git a/python/res/devlib/json/Elite_EIS_1.1.devlib.json b/python/res/devlib/json/Elite_EIS_1.1.devlib.json
index d3f0a5a..23c0849 100644
--- a/python/res/devlib/json/Elite_EIS_1.1.devlib.json
+++ b/python/res/devlib/json/Elite_EIS_1.1.devlib.json
@@ -63,6 +63,7 @@
         "EIS CURVE",
         "Cyclic Voltammetry",
         "Chronoamperometric",
+        "V-T Graph",
         "Dev Mode"
       ]
     },
@@ -277,6 +278,17 @@
         "expression": "VALUE"
       }
     },
+    "MEASURE_VIN_RANGE": {
+      "description": "measure range of Vin",
+      "record_meta": true,
+      "initial": 0,
+      "value": [
+        "0",
+        "1",
+        "2",
+        "auto"
+      ]
+    },
     "BLE_WRITE": {
       "description": "send msg to elite",
       "domain": {
@@ -308,14 +320,16 @@
         "expression": "MODE",
         "when": {
           "1": "set_adc_gain_I",
-          "2": "set_adc_gain_I"
+          "2": "set_adc_gain_I",
+          "3": "set_adc_gain_I"
         }
       },
       {
         "expression": "MODE",
         "when": {
           "1": "set_adc_gain_Vin",
-          "2": "set_adc_gain_Vin"
+          "2": "set_adc_gain_Vin",
+          "3": "set_adc_gain_Vin"
         }
       },
       {
@@ -323,7 +337,8 @@
         "when": {
           "0": "curve_eis",
           "1": "curve_cv3",
-          "2": "curve_const_vscan"
+          "2": "curve_const_vscan",
+          "3": "curve_vt"
         }
       },
       {
@@ -456,6 +471,23 @@
         "2B>pe"
       ]
     },
+    "curve_vt": {
+      "type": "RIS",
+      "parameter": {
+        "pa": "ADC_LEVEL_I_15",
+        "pb": "ADC_LEVEL_V_IN_15",
+        "pd": "CTRL_HIGH_Z_15",
+        "pe": "SAMPLE_RATE",
+        "va": "MEASURE_VIN_RANGE"
+      },
+      "data": [
+        "X05;",
+        "4b>pa;4b>pb;",
+        "4b>0;4b>pd;",
+        "2B>pe;",
+        "1B>va"
+      ]
+    },
     "ble_instru_send": [
       "ble_write",
       "_cdr('20X>ADC_VALUE_I')"
diff --git a/python/res/devlib/json/Elite_EIS_MINI_1.0.devlib.json b/python/res/devlib/json/Elite_EIS_MINI_1.0.devlib.json
index 4c4fa31..006988c 100644
--- a/python/res/devlib/json/Elite_EIS_MINI_1.0.devlib.json
+++ b/python/res/devlib/json/Elite_EIS_MINI_1.0.devlib.json
@@ -63,6 +63,7 @@
         "EIS CURVE",
         "Cyclic Voltammetry",
         "Chronoamperometric",
+        "V-T Graph",
         "Dev Mode"
       ]
     },
@@ -70,7 +71,7 @@
       "description": "DPV current recording period start",
       "record_meta": true,
       "initial": [
-        13422819,
+        13333333,
         7
       ],
       "domain": {
@@ -277,6 +278,17 @@
         "expression": "VALUE"
       }
     },
+    "MEASURE_VIN_RANGE": {
+      "description": "measure range of Vin",
+      "record_meta": true,
+      "initial": 0,
+      "value": [
+        "0",
+        "1",
+        "2",
+        "auto"
+      ]
+    },
     "BLE_WRITE": {
       "description": "send msg to elite",
       "domain": {
@@ -308,14 +320,16 @@
         "expression": "MODE",
         "when": {
           "1": "set_adc_gain_I",
-          "2": "set_adc_gain_I"
+          "2": "set_adc_gain_I",
+          "3": "set_adc_gain_I"
         }
       },
       {
         "expression": "MODE",
         "when": {
           "1": "set_adc_gain_Vin",
-          "2": "set_adc_gain_Vin"
+          "2": "set_adc_gain_Vin",
+          "3": "set_adc_gain_Vin"
         }
       },
       {
@@ -323,7 +337,8 @@
         "when": {
           "0": "curve_eis",
           "1": "curve_cv3",
-          "2": "curve_const_vscan"
+          "2": "curve_const_vscan",
+          "3": "curve_vt"
         }
       },
       {
@@ -456,6 +471,23 @@
         "2B>pe"
       ]
     },
+    "curve_vt": {
+      "type": "RIS",
+      "parameter": {
+        "pa": "ADC_LEVEL_I_15",
+        "pb": "ADC_LEVEL_V_IN_15",
+        "pd": "CTRL_HIGH_Z_15",
+        "pe": "SAMPLE_RATE",
+        "va": "MEASURE_VIN_RANGE"
+      },
+      "data": [
+        "X05;",
+        "4b>pa;4b>pb;",
+        "4b>0;4b>pd;",
+        "2B>pe;",
+        "1B>va"
+      ]
+    },
     "ble_instru_send": [
       "ble_write",
       "_cdr('20X>ADC_VALUE_I')"