diff --git a/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/Elite15_PIN.h b/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/Elite15_PIN.h
index c2d12f732..953cd9631 100644
--- a/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/Elite15_PIN.h
+++ b/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/Elite15_PIN.h
@@ -214,28 +214,6 @@ static void Init_Elite15_PIN () {
     latch_setOutputValue(LOAD0, 0);
 
     remove_elite_pin();
-
-//    InitLH();
-//    add_elite_pin();
-//
-//    PIN_setOutputValue(pin_handle, LOAD0, 1);
-//    PIN_setOutputValue(pin_handle, LOAD1, 1);
-//    PIN_setOutputValue(pin_handle, LOAD2, 1);
-//    CPUdelay(10);
-//    PIN_setOutputValue(pin_handle, D0, 0);
-//    PIN_setOutputValue(pin_handle, D1, 0);
-//    PIN_setOutputValue(pin_handle, D2, 0);
-//    PIN_setOutputValue(pin_handle, D3, 0);
-//    PIN_setOutputValue(pin_handle, D4, 0);
-//    PIN_setOutputValue(pin_handle, D5, 0);
-//    PIN_setOutputValue(pin_handle, D6, 0);
-//    PIN_setOutputValue(pin_handle, D7, 0);
-//    CPUdelay(10);
-//    PIN_setOutputValue(pin_handle, LOAD0, 0);
-//    PIN_setOutputValue(pin_handle, LOAD1, 0);
-//    PIN_setOutputValue(pin_handle, LOAD2, 0);
-//
-//    remove_elite_pin();
 }
 
 static void latch_setOutputValue (uint32_t latch_num, bool highlow) {
@@ -260,12 +238,14 @@ static void latch_setOutputValue (uint32_t latch_num, bool highlow) {
             default: {
                 PIN_setOutputValue(pin_handle, LOADA, 1);
                 PIN_setOutputValue(pin_handle, LOADB, 1);
+//                PIN_setPortOutputValue(pin_handle, ((1<<LOADA)|(1<<LOADB)));
                 break;
             }
         }
     } else {    // All latch turn off
-        PIN_setOutputValue(pin_handle, LOADA, 1);
+        PIN_setOutputValue(pin_handle, LOADA, 1);   // pull LOADB before LOADA
         PIN_setOutputValue(pin_handle, LOADB, 1);
+//        PIN_setPortOutputValue(pin_handle, ((1<<LOADA)|(1<<LOADB)));
     }
 
 }
diff --git a/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/EliteADC.h b/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/EliteADC.h
index f09a07430..b245617da 100644
--- a/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/EliteADC.h
+++ b/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/EliteADC.h
@@ -25,11 +25,6 @@
 #define ADC_CH_DAC          0x02
 #define ADC_CH_BAT          0x03
 
-#define GPIO_CH_0           0x00
-#define GPIO_CH_1           0x01
-#define GPIO_CH_2           0x02
-#define GPIO_CH_3           0x03
-
 #define Aout_CH_0           0x00
 #define Aout_CH_1           0x01
 #define Aout_CH_2           0x02
@@ -629,8 +624,6 @@ static void GPIO_SPI_write(uint8_t GPIO_channel, uint16_t GPIOin) {
         Iout = 1.25/680 * ([9:7] +1)/8 * [6:0]
     */
 
-
-
     static uint32_t TW_CH_0 [2] = {TW_SCKI_0};
     static uint32_t TW_CH_1 [2] = {TW_SCKI_1};
     static uint32_t TW_CH_2 [2] = {TW_SCKI_2};
@@ -638,36 +631,45 @@ static void GPIO_SPI_write(uint8_t GPIO_channel, uint16_t GPIOin) {
 
     uint32_t CLK_CH[2] = {0};
     spi_GPIO_txbuf = 0;
+    bool trans_valid = false;
 
     switch (GPIO_channel) {
-        case GPIO_CH_0: {
+        case Aout_CH_0: {
             CLK_CH[0] = TW_CH_0[0];
             CLK_CH[1] = TW_CH_0[1];
+            trans_valid = true;
             break;
         }
-        case GPIO_CH_1: {
+        case Aout_CH_1: {
             CLK_CH[0] = TW_CH_1[0];
             CLK_CH[1] = TW_CH_1[1];
+            trans_valid = true;
             break;
         }
-        case GPIO_CH_2: {
+        case Aout_CH_2: {
             CLK_CH[0] = TW_CH_2[0];
             CLK_CH[1] = TW_CH_2[1];
+            trans_valid = true;
             break;
         }
-        case GPIO_CH_3: {
+        case Aout_CH_3: {
             CLK_CH[0] = TW_CH_3[0];
             CLK_CH[1] = TW_CH_3[1];
+            trans_valid = true;
             break;
         }
         default: {
+            trans_valid = false;
             break;
         }
     }
 
+    /* GPIOin = 0x0000 ~ 0x0400 */
     spi_GPIO_txbuf = GPIOin;
-    GPIO_SPI_transfer(CLK_CH, spi_GPIO_txbuf);
-
+    if (trans_valid) {
+        GPIO_SPI_transfer(CLK_CH, spi_GPIO_txbuf);
+        trans_valid = false;
+    }
 }
 
 static void AoutChannelSelect(uint8_t Aout_channel, bool on_off) {
@@ -701,10 +703,10 @@ static void AoutChannelSelect(uint8_t Aout_channel, bool on_off) {
 }
 
 static void TW1508reset() {
-    GPIO_SPI_write(GPIO_CH_0, 0x0000);
-    GPIO_SPI_write(GPIO_CH_1, 0x0000);
-    GPIO_SPI_write(GPIO_CH_2, 0x0000);
-    GPIO_SPI_write(GPIO_CH_3, 0x0000);
+    GPIO_SPI_write(Aout_CH_0, 0x0000);
+    GPIO_SPI_write(Aout_CH_1, 0x0000);
+    GPIO_SPI_write(Aout_CH_2, 0x0000);
+    GPIO_SPI_write(Aout_CH_3, 0x0000);
 }
 
 #endif
diff --git a/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/EliteDAC.h b/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/EliteDAC.h
index 3bd7ee376..906ddcff1 100644
--- a/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/EliteDAC.h
+++ b/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/EliteDAC.h
@@ -51,7 +51,7 @@ static uint16_t DAC_outputV(uint16_t voltLV) {
     spi_DACtxbuf[1] = v1;
     spi_DACtxbuf[2] = v2;
 
-    DAC_SPI(SPI_DAC_SIZE, spi_DACtxbuf, spi_rxbuf);
+//    DAC_SPI(SPI_DAC_SIZE, spi_DACtxbuf, spi_rxbuf);
 
     return voltLV;
 }
diff --git a/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/EliteSPI.h b/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/EliteSPI.h
index d689d7f47..ee6cce7d3 100644
--- a/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/EliteSPI.h
+++ b/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/EliteSPI.h
@@ -103,12 +103,14 @@ static void DAC_SPI(uint8_t length, uint8_t *spi_txbuf, uint8_t *spi_rxbuf) {
 static void  ELITE15_SPI_HOLD() {
     Elite_SPI_init();
 
-    PIN_setOutputValue(pin_handle, LOADA, 0);       // Turn on LATCH0
-    PIN_setOutputValue(pin_handle, LOADB, 0);
+//    PIN_setOutputValue(pin_handle, LOADA, 0);       // Turn on LATCH0
+//    PIN_setOutputValue(pin_handle, LOADB, 0);
+    PIN_setPortOutputValue(pin_handle, 0);
 }
 static void ELITE15_SPI_CLOSE() {
-    PIN_setOutputValue(pin_handle, LOADA, 1);       // Turn off all LATCH
-    PIN_setOutputValue(pin_handle, LOADB, 1);
+//    PIN_setOutputValue(pin_handle, LOADB, 1);       // Turn off all LATCH
+//    PIN_setOutputValue(pin_handle, LOADA, 1);
+    PIN_setPortOutputValue(pin_handle, 1);
 
     SPI_close(spiHandle0);
     SPI_close(spiHandle1);
@@ -133,7 +135,7 @@ static void CAL_ADC_SPI(uint8_t length, uint8_t *spi_txbuf, uint8_t *spi_rxbuf)
 
 static void GPIO_SPI_transfer(uint32_t *GPIO_CLK_CH, uint16_t spi_GPIO_txbuf) {
 
-    for(int i=0; i<SPI_GPIO_BUFF_SIZE; i++){
+    for (int i=0; i<SPI_GPIO_BUFF_SIZE; i++) {
         SPI_GPIO[i] = 0;
     }
 
@@ -149,9 +151,11 @@ static void GPIO_SPI_transfer(uint32_t *GPIO_CLK_CH, uint16_t spi_GPIO_txbuf) {
     SPI_GPIO[9] = (spi_GPIO_txbuf & 0b0000001000000000);
 
     ELITE15_SPI_CLOSE();
+    PIN_setPortOutputValue(pin_handle, 0);
     add_elite_pin();
-    PIN_setOutputValue(pin_handle, LOADA, 0);       // Turn on LATCH0
-    PIN_setOutputValue(pin_handle, LOADB, 0);
+//    PIN_setOutputValue(pin_handle, LOADA, 0);       // Turn on LATCH0
+//    PIN_setOutputValue(pin_handle, LOADB, 0);
+
 
     for (int i=SPI_GPIO_BUFF_SIZE-1; i>=0; i--) {
         PIN_setOutputValue(pin_handle, GPIO_CLK_CH[1], 0);    // generate clk signal
@@ -165,9 +169,10 @@ static void GPIO_SPI_transfer(uint32_t *GPIO_CLK_CH, uint16_t spi_GPIO_txbuf) {
     PIN_setOutputValue(pin_handle, D3, 0);
     update_latch_status (ADC_SPI_MOSI, 0);
 
-    PIN_setOutputValue(pin_handle, LOADA, 1);       // Turn off all LATCH
-    PIN_setOutputValue(pin_handle, LOADB, 1);
+//    PIN_setOutputValue(pin_handle, LOADB, 1);       // Turn off all LATCH
+//    PIN_setOutputValue(pin_handle, LOADA, 1);
     remove_elite_pin();
+    PIN_setPortOutputValue(pin_handle, 1);
     ELITE15_SPI_HOLD();
 
 //    PIN15_setOutputValue(ADC_DAC_SPI_MOSI, 0);
diff --git a/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/Elite_TRIG.h b/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/Elite_TRIG.h
index dea64c122..f2bd2ee51 100644
--- a/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/Elite_TRIG.h
+++ b/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/Elite_TRIG.h
@@ -64,4 +64,6 @@ static void trig_callback(PIN_Handle handle, PIN_Id pinId) {
 
 
 
-#endif
\ No newline at end of file
+#endif
+
+
diff --git a/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/headstage.h b/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/headstage.h
index 140b881fa..67722be7d 100644
--- a/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/headstage.h
+++ b/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/headstage.h
@@ -1061,8 +1061,6 @@ static void update_ZM_instruction(uint8 *ins) {
 //            int32_t ADCRealValue = 0;
             uint8_t CIS_buf[9]   = {0};
             uint16_t ADCValueAVG_RAW = 0;
-            uint8_t ADC_input = 0;
-            bool AVG_done = 0;
 
             uint16_t TW1508in = 0;
             TW1508in = ((uint16_t) (ins[5]) << 8 ) | ((uint16_t) (ins[6]));
@@ -1072,9 +1070,9 @@ static void update_ZM_instruction(uint8 *ins) {
                     if(ins[4] == 0xFF) {
                         TW1508reset();
                     } else {
-                        AoutChannelSelect(ins[4], 1);
                         GPIO_SPI_write(ins[4], TW1508in);
-                        AoutChannelSelect(ins[4], 0);
+//                        AoutChannelSelect(ins[4], 1);
+                        PIN15_setOutputValue(AO_MOS_0, 1);
                     }
                     break;
                 }
diff --git a/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/impedance_meter.h b/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/impedance_meter.h
index 1e1b78b24..b7fcec0da 100644
--- a/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/impedance_meter.h
+++ b/simplelink/ble_sdk_2_02_02_25/src/examples/simple_peripheral/cc26xx/app/headstage/impedance_meter.h
@@ -61,6 +61,7 @@ static void ZM_init() {
     VoutGainControl(INSTRUCTION.VoutGainLevel);
     elite_gptimer_open();
 
+    TW1508reset();
 //    TRIG_LED_Init();
     //    PIN_registerIntCb(pin_handle, switch_on_callback);
     //    PIN_setInterrupt(pin_handle, switch_on | PIN_IRQ_POSEDGE);