diff options
Diffstat (limited to 'wirish/io.h')
| -rw-r--r-- | wirish/io.h | 27 |
1 files changed, 18 insertions, 9 deletions
diff --git a/wirish/io.h b/wirish/io.h index 2d22dcd..8dad1d1 100644 --- a/wirish/io.h +++ b/wirish/io.h @@ -35,10 +35,6 @@ #include "adc.h" #include "time.h" -#ifdef __cplusplus -extern "C"{ -#endif - /** * Specifies a GPIO pin behavior. * @@ -68,11 +64,11 @@ typedef enum WiringPinMode { supply through a large resistor). When the pin is high, not much current flows through to ground and the line stays at positive - voltage; when the pin is low the bus + voltage; when the pin is low, the bus "drains" to ground with a small amount of current constantly flowing through the large resistor from the external supply. In this - mode no current is ever actually /sourced/ + mode, no current is ever actually sourced from the pin. */ INPUT, /**< Basic digital input. The pin voltage is sampled; when @@ -220,8 +216,21 @@ uint8 isButtonPressed(); */ uint8 waitForButtonPress(uint32 timeout_millis); -#ifdef __cplusplus -} // extern "C" -#endif +/** + * Shift out a byte of data, one bit at a time. + * + * This function starts at either the most significant or least + * significant bit in a byte value, and shifts out each byte in order + * onto a data pin. After each bit is written to the data pin, a + * separate clock pin is pulsed to indicate that the new bit is + * available. + * + * @param dataPin Pin to shift data out on + * @param clockPin Pin to pulse after each bit is shifted out + * @param bitOrder Either MSBFIRST (big-endian) or LSBFIRST (little-endian). + * @param val Value to shift out + */ +void shiftOut(uint8 dataPin, uint8 clockPin, uint8 bitOrder, uint8 value); + #endif |