> For the complete documentation index, see [llms.txt](https://sandbox-docs.verifone.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://sandbox-docs.verifone.com/adk-5.0-programmers-guide/gpio_8h_source.md).

# gpio.h

[Go to the documentation of this file.](/adk-5.0-programmers-guide/readme/files/dir_078666aaafc812ef0db017f3778c7af8/dir_1de2fc103c37f88e22147e598fb72856/dir_89bef91478a81057cacdced47a78082e/gpio_8h.md)

```cpp
 1 #ifndef GPIO_H_20230622
 2 #define GPIO_H_20230622
 3 
 4 #if defined _WIN32 && defined VFI_GPIO_EXPORT
 5 # define DllSpec __declspec(dllexport)
 6 #elif defined __GNUC__ && defined VFI_GPIO_EXPORT
 7 # define DllSpec __attribute__((visibility ("default")))
 8 #else
 9 # define DllSpec
 10 #endif
 11 
 12 namespace vfigpio {
 13 
 15 enum GPIO_Error {
 16  GPIOE_OK =0x00,
 17  GPIOE_NOT_CONNECTED =0x01,
 18  GPIOE_IO_ERROR =0x02,
 19  GPIOE_PROTOCOL =0x03,
 20  GPIOE_INVALID_TLV =0x04,
 21  GPIOE_RESET =0x05,
 23  GPIOE_ERROR =0x10,
 24  GPIOE_MESSAGE_TOO_LARGE=0x11,
 25  GPIOE_INVALID_COMMAND =0x12,
 26  GPIOE_INVALID_PARAM =0x13,
 27  GPIOE_CANCELLED =0x14,
 28  GPIOE_NO_RESOURCE =0x15,
 29  GPIOE_BUSY =0x1A,
 30  GPIOE_INVALID_SEQUENCE =0x1C,
 31  GPIOE_TIMEOUT =0x1D,
 32  GPIOE_NOT_FOUND =0x1F,
 34  GPIOE_EVENT_GPIO_1 =0x8005,
 35  GPIOE_EVENT_GPIO_2 =0x8006,
 36  GPIOE_EVENT_GPIO_3 =0x8007,
 37  GPIOE_EVENT_GPIO_4 =0x8008,
 38 };
 39 
 41 enum GPIO_Config {
 42  GPIO_OUTPUT=1,
 43  GPIO_DEBOUNCE=2,
 44 };
 45 
 47 enum GPIO_EventMask {
 48  GPIO_EVENT_GPIO_1 =0x0010,
 49  GPIO_EVENT_GPIO_2 =0x0020,
 50  GPIO_EVENT_GPIO_3 =0x0040,
 51  GPIO_EVENT_GPIO_4 =0x0080,
 52 };
 53 
 54 
 55 class DllSpec GPIO {
 56  public:
 57  class GPIOPrivate;
 58  private:
 59  GPIOPrivate *d; // PIMPL data pointer
 60 
 61  // prevent copying objects
 62  GPIO(const GPIO &o);
 63  void operator=(const GPIO &o);
 64 
 65  public:
 66 
 70  static GPIO &DefaultLink();
 71 
 73  GPIO();
 74 
 76  virtual ~GPIO();
 77 
 82  GPIO_Error connect(const char *name);
 83 
 86  void disconnect();
 87 
 88  enum TraceType { SEND_HEADER,SEND_DATA,RECEIVE_HEADER,RECEIVE_DATA };
 89  typedef void (*TraceFunc)(void *data, TraceType dir, const void *buffer, unsigned size);
 90 
 95  void setTrace(TraceFunc t, void *data);
 96 
 97  /*******************************************************/
 98  /************************ GPIO *************************/
 99  /*******************************************************/
 100 
 110  GPIO_Error setConfig(int pin, unsigned config, bool initval=false);
 111 
 116  GPIO_Error getConfig(int pin, unsigned &config);
 117 
 123  GPIO_Error read(int pin, bool &value);
 124 
 130  GPIO_Error write(int pin, bool value);
 131 
 136  static bool isFinalResult(int r) { return r<0x8000; }
 137 
 152  GPIO_Error startAsyncRead(void *&handle,
 153  unsigned mask,
 154  void (*cb)(void *data, int result, int value),
 155  void *data);
 156 
 161  GPIO_Error stopAsyncRead(void *handle);
 162 
 167  GPIO_Error setExtPrtPower(bool on);
 168 
 173  GPIO_Error getExtPrtPower(bool &on);
 174 
 175 };
 176 
 177 
 178 } // namespace
 179 
 180 #undef DllSpec
 181 
 182 #endif
```


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