Arduino Cryptography Library
TransistorNoiseSource.h
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22 
23 #ifndef CRYPTO_TRANSISTORNOISESOURCE_H
24 #define CRYPTO_TRANSISTORNOISESOURCE_H
25 
26 #include <inttypes.h>
27 #include "NoiseSource.h"
28 
30 {
31 public:
32  explicit TransistorNoiseSource(uint8_t pin);
33  virtual ~TransistorNoiseSource();
34 
35  bool calibrating() const;
36 
37  void stir();
38 
39 private:
40  int threshold;
41  uint8_t _pin;
42  uint8_t prevBit;
43  uint8_t posn;
44  uint8_t bitNum;
45  uint8_t calState;
46  uint8_t buffer[32];
47  int minValue;
48  int maxValue;
49  int count;
50  int ones;
51 
52  void restart();
53 };
54 
55 #endif
Abstract base class for random noise sources.
Definition: NoiseSource.h:30
Processes the signal from a transistor-based noise source.
TransistorNoiseSource(uint8_t pin)
Constructs a new transitor-based noise source handler.
bool calibrating() const
Determine if the noise source is still calibrating itself.
void stir()
Stirs entropy from this noise source into the global random number pool.