fix for direction pin levels and self containing example

examples/x9cSetAndRead/x9cSetAndRead.ino

@@ -0,0 +1,66 @@
+/* 
+   Digital potentiometer X9C103S control
+
+   This example controls digital potentiometer X9C103S module by seting its
+   wiper position from 0 till 99. At the same time Arduino reads wiper pin
+   value using its analog pin.
+   Program outputs calculated theoretical and read values.
+
+   The circuit:
+         Arduino    X9C103S module
+              5V -> Vcc
+             GND -> GND
+   digital pin 5 -> INC increment input
+   digital pin 6 -> U/D up/down input
+   digital pin 7 -> CS  chip select input
+              5V -> VH  high terminal
+   analog pin A0 -> VW  wiper terminal
+             GND -> VL  low terminal
+ */
+
+#include <X9C.h>
+
+const int INC = 5; // Arduino digital pin 5 connected to module increment 
+                   // input pin INC
+const int UD = 6;  // Arduino digital pin 6 connected to module up/down
+                   // input pin U/D
+const int CS = 7;  // Arduino digital pin 7 connected to module chip select
+                   // input pin CS
+const int wiperPin = A0; // Arduino analog pin A0 connected to the module
+                         // wiper pin Vw/Rw
+const float Vcc = 4930.0f; // voltage between GND and Arduino Aref pin measured
+                           // with voltmeter (mV)
+const float VccDiv99 = Vcc/99.0f; // theoretical voltage increment per one
+                                  // digital potentiometer step (mV)
+const float VccDiv1024 = Vcc/1024.0f; // voltage step size for Arduino analog
+                                      // pin (mv)
+
+X9C pot; // create a pot controller
+int sensorValue = 0; // variable to store the value coming from analog pin
+                     // (range from 0 to 1023)
+void setup() {
+  Serial.begin(9600);
+  while (!Serial);// wait for serial port to connect
+  pot.begin(CS,INC,UD); //setup pot pins
+  Serial.println("Pot_step A0_value PotSet_mV PotRead_mV");
+  for(uint8_t potStep=0;potStep<100;potStep++){
+    if(potStep==0){
+      pot.setPotMin(false); //begin with known position
+    }else{
+      pot.trimPot(1,X9C_UP); // increment pot value
+    }
+    sensorValue = analogRead(wiperPin); // read real pot value
+    //report
+    Serial.print(potStep);
+    Serial.print(" ");
+    Serial.print(sensorValue);
+    Serial.print(" ");
+    Serial.print(((float)potStep)*VccDiv99);
+    Serial.print(" ");
+    Serial.println(((float)sensorValue)*VccDiv1024);    
+    delay(200);
+  }
+}
+
+void loop(){
+}

src/X9C.h

@@ -30,8 +30,8 @@ SOFTWARE.
 //
 #include <Arduino.h>
 
-#define X9C_UP LOW
-#define X9C_DOWN HIGH
+#define X9C_UP HIGH
+#define X9C_DOWN LOW
 #define X9C_MAX 99
 //
 // stepPot explicilty does NOT save to NVRAM - allows reboot to old NVRAM value, with minor runtime tweaks