struct _am7xxx_context;
typedef struct _am7xxx_context am7xxx_context;
-/**
+/**
* @typedef am7xxx_device
*
* An opaque data type representing an am7xxx device.
* 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.
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.
* 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
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
unsigned int image_size);
/**
- * Set the power mode of an am7xxx device.
+ * Queue transfer of an image for display on an am7xxx device and return immediately.
*
- * \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.
+ * 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
+ * until another image get sent or some command resets or turns off the display.
+ *
+ * @note This _async() variant makes a copy of the image buffer, so the caller
+ * is free to reuse the buffer just after the function returns.
*
* @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] format The format the image is in (see @link am7xxx_image_format @endlink enum)
+ * @param[in] width The width of the image
+ * @param[in] height The height of the image
+ * @param[in] image A buffer holding data in the format specified by the format parameter
+ * @param[in] image_size The size in bytes of the image buffer
+ *
+ * @return 0 on success, a negative value on error
+ */
+int am7xxx_send_image_async(am7xxx_device *dev,
+ am7xxx_image_format format,
+ unsigned int width,
+ unsigned int height,
+ unsigned char *image,
+ unsigned int image_size);
+
+/**
+ * Set the power mode of an am7xxx 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 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
}
projects / libam7xxx.git / blobdiff