The UHC provides a high-level abstraction of the usb host.
You can use these functions to control the main host state (start/suspend/resume/...).
All USB Host Interface (UHI) in USB Host Stack is based on UHC to support USB enumeration.
For more details for Atmel Software Framework (ASF) USB Host Stack, refer to following application note:
This documentation describes common USB Host usage based on UHC, as follow:
Data Structures | |
| struct | uhc_device_t |
| Structure to store device information. More... | |
Enumerations | |
| enum | uhc_enum_status_t { UHC_ENUM_SUCCESS = 0, UHC_ENUM_UNSUPPORTED, UHC_ENUM_OVERCURRENT, UHC_ENUM_FAIL, UHC_ENUM_HARDWARE_LIMIT, UHC_ENUM_SOFTWARE_LIMIT, UHC_ENUM_MEMORY_LIMIT, UHC_ENUM_DISCONNECT } |
| Enumeration status Used in UHC_ENUM_EVENT() callback when a USB device enumeration is completed. More... | |
Functions to Control the USB Host Stack | |
| void | uhc_start (void) |
| Starts the host mode. More... | |
| void | uhc_stop (bool b_id_stop) |
| Stops the host mode. More... | |
| void | uhc_suspend (bool b_remotewakeup) |
| Suspends a USB line. More... | |
| bool | uhc_is_suspend (void) |
| Test if the suspend state is enabled on the USB line. More... | |
| void | uhc_resume (void) |
| Resumes the USB line. More... | |
| bool | uhc_suspend_lpm (bool b_remotewakeup, uint8_t hird) |
| Suspends a USB line through LPM feature(SAM D21). More... | |
User Functions to Manage a Device | |
| uint8_t | uhc_get_device_number (void) |
| Returns the number of connected devices. More... | |
| char * | uhc_dev_get_string_manufacturer (uhc_device_t *dev) |
| Gets the USB string manufacturer from a USB device. More... | |
| char * | uhc_dev_get_string_product (uhc_device_t *dev) |
| Gets the USB string product from a USB device. More... | |
| char * | uhc_dev_get_string_serial (uhc_device_t *dev) |
| Gets the USB string serial from a USB device. More... | |
| char * | uhc_dev_get_string (uhc_device_t *dev, uint8_t str_id) |
| Gets a USB string from a USB device. More... | |
| uint16_t | uhc_dev_get_power (uhc_device_t *dev) |
| Gets the maximum consumption of a device (mA). More... | |
| uhd_speed_t | uhc_dev_get_speed (uhc_device_t *dev) |
| Returns the current device speed. More... | |
| bool | uhc_dev_is_high_speed_support (uhc_device_t *dev) |
| Tests if the device supports the USB high speed. More... | |
| enum uhc_enum_status_t |
Enumeration status Used in UHC_ENUM_EVENT() callback when a USB device enumeration is completed.
| uint16_t uhc_dev_get_power | ( | uhc_device_t * | dev | ) |
Gets the maximum consumption of a device (mA).
| [in] | dev | Device to request. |
| uhd_speed_t uhc_dev_get_speed | ( | uhc_device_t * | dev | ) |
Returns the current device speed.
| [in] | dev | Device to request. |
| char* uhc_dev_get_string | ( | uhc_device_t * | dev, |
| uint8_t | str_id | ||
| ) |
Gets a USB string from a USB device.
This function waits the end of setup requests and the timing can be long (3ms to 15s). Thus, do not call it in an interrupt routine. This function allocates a buffer which must be free by user application.
| [in] | dev | Device to request. |
| [in] | str_id | String ID requested. |
| char* uhc_dev_get_string_manufacturer | ( | uhc_device_t * | dev | ) |
Gets the USB string manufacturer from a USB device.
This function waits the end of setup requests and the timing can be long (3ms to 15s). Thus, do not call it in an interrupt routine. This function allocates a buffer which must be free by user application.
| [in] | dev | Device to request. |
| char* uhc_dev_get_string_product | ( | uhc_device_t * | dev | ) |
Gets the USB string product from a USB device.
This function waits the end of setup requests and the timing can be long (3ms to 15s). Thus, do not call it in an interrupt routine. This function allocates a buffer which must be free by user application.
| [in] | dev | Device to request. |
| char* uhc_dev_get_string_serial | ( | uhc_device_t * | dev | ) |
Gets the USB string serial from a USB device.
This function waits the end of setup requests and the timing can be long (3ms to 15s). Thus, do not call it in an interrupt routine. This function allocates a buffer which must be free by user application.
| [in] | dev | Device to request. |
| bool uhc_dev_is_high_speed_support | ( | uhc_device_t * | dev | ) |
Tests if the device supports the USB high speed.
This function can wait the end of a setup request and the timing can be long (1ms to 5s). Thus, do not call it in an interrupt routine.
| [in] | dev | Device to request. |
| uint8_t uhc_get_device_number | ( | void | ) |
Returns the number of connected devices.
| bool uhc_is_suspend | ( | void | ) |
Test if the suspend state is enabled on the USB line.
| void uhc_resume | ( | void | ) |
Resumes the USB line.
| void uhc_start | ( | void | ) |
Starts the host mode.
| void uhc_stop | ( | bool | b_id_stop | ) |
Stops the host mode.
| [in] | b_id_stop | Stop USB ID pin management, if true. |
| void uhc_suspend | ( | bool | b_remotewakeup | ) |
Suspends a USB line.
| [in] | b_remotewakeup | Authorize the remote wakeup features, if true. |
| bool uhc_suspend_lpm | ( | bool | b_remotewakeup, |
| uint8_t | hird | ||
| ) |
Suspends a USB line through LPM feature(SAM D21).
| [in] | b_remotewakeup | Authorize the remote wakeup features, if true. |
| [in] | hird | Host Initiated Resume Duration. |
1.8.5