Ring oscillator noise source class

libraries/Crypto/examples/TestTransistorNoise/TestTransistorNoise.ino

@@ -0,0 +1,44 @@
+
+// This example dumps the raw data from a transistor noise source
+// without any of the whitening normally performed by the RNG class.
+
+#include <Crypto.h>
+#include <TransistorNoiseSource.h>
+
+char const hexchars[] = "0123456789ABCDEF";
+
+class RawNoiseSource : public TransistorNoiseSource
+{
+public:
+    RawNoiseSource(uint8_t pin) : TransistorNoiseSource(pin) {}
+
+protected:
+    void output(const uint8_t *data, size_t len, unsigned int credit)
+    {
+        for (size_t posn = 0; posn < len; ++posn) {
+            uint8_t value = data[posn];
+            Serial.print(hexchars[(value >> 4) & 0x0F]);
+            Serial.print(hexchars[value & 0x0F]);
+        }
+        Serial.println();
+    }
+};
+
+RawNoiseSource noise(A1);
+bool calibrating = true;
+
+void setup() {
+    Serial.begin(9600);
+    Serial.println();
+    Serial.println("calibrating");
+}
+
+void loop() {
+    noise.stir();
+    bool nowCalibrating = noise.calibrating();
+    if (nowCalibrating != calibrating) {
+        calibrating = nowCalibrating;
+        if (calibrating)
+            Serial.println("calibrating");
+    }
+}