am7xxx: fix a typo in a comment s/a am7xxx device/an am7xxx device/

[libam7xxx.git] / src / am7xxx.h

diff --git a/src/am7xxx.h b/src/am7xxx.h
index df305e5..1c353ab 100644 (file)
--- a/src/am7xxx.h
+++ b/src/am7xxx.h
@@ -37,7 +37,7 @@ extern "C" {
 struct _am7xxx_context;
 typedef struct _am7xxx_context am7xxx_context;
 
-/** 
+/**
  * @typedef am7xxx_device
  *
  * An opaque data type representing an am7xxx device.
@@ -88,7 +88,7 @@ typedef enum {
  * An am7xxx device can operate in several power modes. A certain power mode
  * may have effect on the display brightness or on the device power
  * consumption.
- *             
+ *
  * @note Most am7xxx devices come with a Y-shaped USB cable with a Master and
  * a Slave connector, higher power modes may require that both connectors are
  * plugged in to the host system for the device to work properly.
@@ -99,12 +99,30 @@ typedef enum {
 typedef enum {
        AM7XXX_POWER_OFF    = 0, /**< Display is powered off, no image shown. */
        AM7XXX_POWER_LOW    = 1, /**< Low power consumption but also low brightness. */
-       AM7XXX_POWER_MIDDLE = 2, /**< Middle level of brightness. */
+       AM7XXX_POWER_MIDDLE = 2, /**< Middle level of brightness. This and upper modes need both the Master and Slave USB connectors plugged. */
        AM7XXX_POWER_HIGH   = 3, /**< More brightness, but more power consumption. */
-       AM7XXX_POWER_TURBO  = 4, /**< Max brightness and power consumprion. This may need both the Master and Slave USB connectors plugged. */
+       AM7XXX_POWER_TURBO  = 4, /**< Max brightness and power consumption. */
 } am7xxx_power_mode;
 
 /**
+ * The display zoom modes.
+ *
+ * An am7xxx device can display images using several zoom modes.
+ *
+ * @note Changing the zoom mode can change the aspect ratio of the displayed
+ * image.
+ *
+ * @note On the zoom test screen the version of the firmware running on the
+ * device is shown as well (e.g SPI_V21.0.0_2011.03.18).
+ */
+typedef enum {
+       AM7XXX_ZOOM_ORIGINAL = 0, /**< Original Size, as retrieved via #am7xxx_device_info. */
+       AM7XXX_ZOOM_H        = 1, /**< Zoom 1: H Scale (changes aspect ratio). */
+       AM7XXX_ZOOM_H_V      = 2, /**< Zoom 2: H/V Scale (changes aspect ratio). */
+       AM7XXX_ZOOM_TEST     = 3, /**< Zoom test screen, the firmware version is shown as well. */
+} am7xxx_zoom_mode;
+
+/**
  * Initialize the library context and data structures, and scan for devices.
  *
  * @param[out] ctx A pointer to the context the library will be used in.
@@ -184,9 +202,9 @@ int am7xxx_get_device_info(am7xxx_device *dev,
  * Before sending images bigger than the device native dimensions the user
  * needs to rescale them, this utility function does the calculation in a way
  * that the original image aspect ratio is preserved.
- * 
+ *
  * @param[in] dev A pointer to the structure representing the device to get info of
- * @param[in] upscale Whether to calculate scaled dimensions for images smaller than the native dimesions
+ * @param[in] upscale Whether to calculate scaled dimensions for images smaller than the native dimensions
  * @param[in] original_width The width of the original image
  * @param[in] original_height The height of the original image
  * @param[out] scaled_width The width the rescaled image should have
@@ -201,7 +219,7 @@ int am7xxx_calc_scaled_image_dimensions(am7xxx_device *dev,
                                        unsigned int *scaled_width,
                                        unsigned int *scaled_height);
 /**
- * Send an image for display on a am7xxx device.
+ * Send an image for display on an am7xxx device.
  *
  * This is the function that actually makes the device display something.
  * Static pictures can be sent just once and the device will keep showing them
@@ -226,17 +244,38 @@ int am7xxx_send_image(am7xxx_device *dev,
 /**
  * Set the power mode of an am7xxx device.
  *
- * \note If we set the mode to AM7XXX_POWER_OFF we can't turn the
- * display on again by using only am7xxx_set_power_mode(). This needs to be
- * investigated, maybe some other command can reset the device.
+ * @note When setting the mode to AM7XXX_POWER_OFF the display can't be turned
+ * on again by using only am7xxx_set_power_mode(), am7xxx_set_zoom_mode() has
+ * to be called first, the current guess is that the latter performs some
+ * other resets beside setting the zoom mode.
  *
- * @param[in] dev A pointer to the structure representing the device to get info of
- * @param[in] mode The power mode to put the device in (see @link am7xxx_power_mode @endlink enum)
+ * @param[in] dev A pointer to the structure representing the device to set power mode to
+ * @param[in] power The power mode to put the device in (see #am7xxx_power_mode enum)
+ *
+ * @return 0 on success, a negative value on error
+ *
+ */
+int am7xxx_set_power_mode(am7xxx_device *dev, am7xxx_power_mode power);
+
+/**
+ * Set the zoom mode of an am7xxx device.
+ *
+ * @note When setting the mode to AM7XXX_ZOOM_TEST, the calling program might
+ * want to skip displaying actual images.
+ *
+ * @note It looks like that power mode and zoom mode are related somehow wrt.
+ * resetting the operational mode after AM7XXX_POWER_OFF, applications can
+ * restore the display properly using this combination:
+ *  - Off: power mode 0, zoom mode 3
+ *  - On: power mode != 0, zoom mode != 3
+ *
+ * @param[in] dev A pointer to the structure representing the device to set zoom mode to
+ * @param[in] zoom The zoom mode to put the device in (see #am7xxx_zoom_mode enum)
  *
  * @return 0 on success, a negative value on error
  *
  */
-int am7xxx_set_power_mode(am7xxx_device *dev, am7xxx_power_mode mode);
+int am7xxx_set_zoom_mode(am7xxx_device *dev, am7xxx_zoom_mode zoom);
 
 #ifdef __cplusplus
 }