1 files changed, 70 insertions, 5 deletions
diff --git a/GPIO.h b/GPIO.h
index 0c7ba72..974a778 100644
--- a/GPIO.h
+++ b/GPIO.h
@@ -1,35 +1,100 @@
+/*! \defgroup gpio GPIO
+ * \brief General-purpose input/output
+ *
+ * This module defines macros for input/output pins of microcontroller.
+ * Pin is specified with SET and PIN. SET is letter and PIN is number. Combination
+ * of SET and PIN specifies hardware pin. You can find it in documentation.
+ *
+ * To use this module:
+ *
+ *     #include "avr-ioe/GPIO.h"
+ */
 #include <avr/io.h>
 #include <stdint.h>
 
+#ifdef IOE_CONFIG
+#include <AVR-IOE-CONFIG.h>
+#endif /* IOE_CONFIG */
+
 #ifndef _IOE_GPIO_H_
 #define _IOE_GPIO_H_
 
 #define __GPIO_JOIN2(TXT1, TXT2) TXT1##TXT2
 #define __GPIO_JOIN3(TXT1, TXT2, TXT3) TXT1##TXT2##TXT3
 
+/*! \ingroup gpio
+ * Return direction of specified pin. Pin is set as output if value is nonzero
+ * and as input if returned value is zero.
+ */
 #define gpio_get_mode(SET, PIN)                                                 \
     __GPIO_JOIN2(DDR, SET) & _BV(__GPIO_JOIN3(DD, SET, PIN))
 
-// GPIO output section
+/*! \ingroup gpio
+ * Set specified pin as output.
+ * \param SET -- pin set (letter)
+ * \param PIN -- pin number (number)
+ */
 #define gpio_set_out(SET, PIN)                                                  \
     __GPIO_JOIN2(DDR, SET) |= _BV(__GPIO_JOIN3(DD, SET, PIN))
 
+/*! \ingroup gpio
+ * Set specific pin as input.
+ * \param SET -- pin set (letter)
+ * \param PIN -- pin number (number)
+ */
+#define gpio_set_in(SET, PIN)                                                   \
+    __GPIO_JOIN2(DDR, SET) &= ~_BV(__GPIO_JOIN3(DD, SET, PIN))
+
+// -- GPIO output section --
+/*! \defgroup gpio_out GPIO output
+ * \ingroup gpio
+ */
+/*! \ingroup gpio_out
+ * Set pin high. Pin must be set as output. Undefined behavior for non
+ * output pins.
+ * \param SET -- pin set (letter)
+ * \param PIN -- pin number (number)
+ */
 #define gpio_set_high(SET, PIN)                                                 \
     __GPIO_JOIN2(PORT, SET) |= _BV(__GPIO_JOIN3(PORT, SET, PIN))
 
+/*! \ingroup gpio_out
+ * Set pin low. Pin must be set as output. Undefined behavior for non output pins.
+ * \param SET -- pin set (letter)
+ * \param PIN -- pin number (number)
+ */
 #define gpio_set_low(SET, PIN)                                                  \
     __GPIO_JOIN2(PORT, SET) &= ~_BV(__GPIO_JOIN3(PORT, SET, PIN))
 
+/*! \ingroup gpio_out
+ * Set pin according to \a VALUE. Pin must be set as output. Undefined behavior
+ * for non output pins.
+ * \warning Use this only if VALUE is runtime variable. For constants are prefered
+ * gpio_set_high() and gpio_set_low().
+ * \param SET -- pin set (letter)
+ * \param PIN -- pin number (number)
+ * \param VALUE -- runtime variable or boolean expression used in boolean context.
+ */
 #define gpio_set(SET, PIN, VALUE)                                               \
-    if (value)                                                                  \
+    if (VALUE)                                                                  \
         gpio_set_high(SET, PIN);                                                \
     else                                                                        \
         gpio_set_low(SET, PIN);
 
-// GPIO input section
-#define gpio_set_in(SET, PIN)                                                   \
-    __GPIO_JOIN2(DDR, SET) &= ~_BV(__GPIO_JOIN3(DD, SET, PIN))
+/*! \ingroup gpio_out
+ * Set pin opposite state. If it is set as high it will be low and if it is set
+ * as low it will be high. Pin must be set as output. Undefined behavior for non
+ * output pins.
+ * \param SET -- pin set (letter)
+ * \param PIN -- pin number (number)
+ */
+#define gpio_set_not(SET, PIN)                                                  \
+    __GPIO_JOIN2(PORT, SET) ^= _BV(__GPIO_JOIN3(PORT, SET, PIN))
 
+// -- GPIO input section --
+/*! \defgroup gpio_in GPIO input
+ * \ingroup gpio
+ */
 // TODO whole output and switching betwen input and output
 
 #endif /* _IOE_GPIO_H_ */