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Dependents: TYBLE16_simple_data_logger TYBLE16_MP3_Air
USBAudio Class Reference
[USBAudio class]
#include <USBAudio.h>
Inherits USBDevice.
Public Member Functions | |
USBAudio (bool connect=true, uint32_t frequency_rx=48000, uint8_t channel_count_rx=1, uint32_t frequency_tx=8000, uint8_t channel_count_tx=1, uint32_t buffer_ms=10, uint16_t vendor_id=0x7bb8, uint16_t product_id=0x1111, uint16_t product_release=0x0100) | |
Basic constructor. | |
USBAudio (USBPhy *phy, uint32_t frequency_rx, uint8_t channel_count_rx, uint32_t frequency_tx, uint8_t channel_count_tx, uint32_t buffer_ms, uint16_t vendor_id, uint16_t product_id, uint16_t product_release) | |
Fully featured constructor. | |
virtual | ~USBAudio () |
Destroy this object. | |
void | connect () |
Connect USBAudio. | |
void | disconnect () |
Disconnect USBAudio. | |
bool | read (uint8_t *buf, uint32_t size) |
Read audio data. | |
void | read_nb (uint8_t *buf, uint32_t size, uint32_t *actual) |
Nonblocking audio data read. | |
uint32_t | read_overflows (bool clear=false) |
Return the number read packets dropped due to overflow. | |
bool | read_ready () |
Check if the audio read channel is open. | |
void | read_wait_ready () |
Wait until the audio read channel is open. | |
bool | write (uint8_t *buf, uint32_t size) |
Write audio data. | |
void | write_nb (uint8_t *buf, uint32_t size, uint32_t *actual) |
Nonblocking audio data write. | |
uint32_t | write_underflows (bool clear=false) |
Return the number write packets not sent due to underflow. | |
bool | write_ready () |
Check if the audio write channel is open. | |
void | write_wait_ready () |
Wait until the audio write channel is open. | |
float | get_volume () |
Get current volume between 0.0 and 1.0. | |
void | attach (mbed::Callback< void()> &cb) |
Attach a Callback to update the volume. | |
void | attach_tx (mbed::Callback< void(AudioEvent)> &cb) |
attach a Callback to Tx Done | |
void | attach_rx (mbed::Callback< void(AudioEvent)> &cb) |
attach a Callback to Rx Done | |
Protected Member Functions | |
virtual void | callback_state_change (DeviceState new_state) |
Called when USB changes state. | |
virtual void | callback_request (const setup_packet_t *setup) |
Called by USBDevice on Endpoint0 request. | |
virtual void | callback_request_xfer_done (const setup_packet_t *setup, bool aborted) |
Called by USBDevice on data stage completion. | |
void | init () |
Initialize this instance. | |
void | deinit () |
Power down this instance. | |
bool | configured () |
Check if the device is configured. | |
void | sof_enable () |
Enable the start of frame interrupt. | |
void | sof_disable () |
Disable the start of frame interrupt. | |
bool | endpoint_add (usb_ep_t endpoint, uint32_t max_packet, usb_ep_type_t type, mbed::Callback< void()> callback=NULL) |
Add an endpoint. | |
template<typename T > | |
bool | endpoint_add (usb_ep_t endpoint, uint32_t max_packet, usb_ep_type_t type, void(T::*callback)()) |
Add an endpoint. | |
void | endpoint_remove (usb_ep_t endpoint) |
Remove an endpoint. | |
void | endpoint_remove_all () |
Remove all non-zero endpoints. | |
void | endpoint_stall (usb_ep_t endpoint) |
Stall an endpoint. | |
void | endpoint_unstall (usb_ep_t endpoint) |
Un-stall an endpoint. | |
uint32_t | endpoint_max_packet_size (usb_ep_t endpoint) |
Get the current maximum size for this endpoint. | |
void | endpoint_abort (usb_ep_t endpoint) |
Abort the current transfer on this endpoint. | |
bool | read_start (usb_ep_t endpoint, uint8_t *buffer, uint32_t size) |
start a read on the given endpoint | |
uint32_t | read_finish (usb_ep_t endpoint) |
Get the status of a read. | |
bool | write_start (usb_ep_t endpoint, uint8_t *buffer, uint32_t size) |
Write a data to the given endpoint. | |
uint32_t | write_finish (usb_ep_t endpoint) |
Get the status of a write. | |
virtual void | callback_power (bool powered) |
Called by USBDevice layer on power state change. | |
virtual void | callback_sof (int frame_number) |
Called by USBDevice layer on each new USB frame. | |
virtual void | callback_reset () |
Called by USBDevice layer on bus reset. | |
void | complete_request (RequestResult result, uint8_t *data=NULL, uint32_t size=0) |
Called to complete the setup stage of a callback request. | |
void | complete_request_xfer_done (bool success) |
Called to complete the data stage of a callback request. | |
void | complete_set_configuration (bool success) |
Called to complete a set configuration command. | |
void | complete_set_interface (bool success) |
Called to complete a set interface command. | |
uint8_t * | find_descriptor (uint8_t descriptor_type, uint8_t index=0) |
Find a descriptor type inside the configuration descriptor. | |
const usb_ep_table_t * | endpoint_table () |
Get the endpoint table of this device. | |
virtual void | start_process () |
Callback called to indicate the USB processing needs to be done. | |
virtual void | lock () |
Acquire exclusive access to this instance USBDevice. | |
virtual void | unlock () |
Release exclusive access to this instance USBDevice. | |
virtual void | assert_locked () |
Assert that the current thread of execution holds the lock. |
Detailed Description
USBAudio example.
#include "mbed.h" #include "USBAudio.h" // Audio loopback example use: // 1. Select "Mbed Audio" as your sound device // 2. Play a song or audio file // 3. Record the output using a program such as Audacity int main() { USBAudio audio(true, 44100, 2, 44100, 2); printf("Looping audio\r\n"); static uint8_t buf[128]; while (true) { if (!audio.read(buf, sizeof(buf))) { memset(buf, 0, sizeof(buf)); } audio.write(buf, sizeof(buf)); } }
Definition at line 69 of file USBAudio.h.
Constructor & Destructor Documentation
USBAudio | ( | bool | connect = true , |
uint32_t | frequency_rx = 48000 , |
||
uint8_t | channel_count_rx = 1 , |
||
uint32_t | frequency_tx = 8000 , |
||
uint8_t | channel_count_tx = 1 , |
||
uint32_t | buffer_ms = 10 , |
||
uint16_t | vendor_id = 0x7bb8 , |
||
uint16_t | product_id = 0x1111 , |
||
uint16_t | product_release = 0x0100 |
||
) |
Basic constructor.
Construct this object optionally connecting.
- Note:
- Do not use this constructor in derived classes.
- Parameters:
-
connect Call connect on initialization frequency_rx frequency in Hz (default: 48000) channel_count_rx channel number (1 or 2) (default: 1) frequency_tx frequency in Hz (default: 8000) channel_count_tx channel number (1 or 2) (default: 1) buffer_ms time audio can be buffered without overflowing in milliseconds vendor_id Your vendor_id product_id Your product_id product_release Your product_release
Definition at line 119 of file USBAudio.cpp.
USBAudio | ( | USBPhy * | phy, |
uint32_t | frequency_rx, | ||
uint8_t | channel_count_rx, | ||
uint32_t | frequency_tx, | ||
uint8_t | channel_count_tx, | ||
uint32_t | buffer_ms, | ||
uint16_t | vendor_id, | ||
uint16_t | product_id, | ||
uint16_t | product_release | ||
) |
Fully featured constructor.
Construct this object with the supplied USBPhy and parameters. The user this object is responsible for calling connect() or init().
- Note:
- Derived classes must use this constructor and call init() or connect() themselves. Derived classes should also call deinit() in their destructor. This ensures that no interrupts can occur when the object is partially constructed or destroyed.
- Parameters:
-
phy USB phy to use frequency_rx frequency in Hz (default: 48000) channel_count_rx channel number (1 or 2) (default: 1) frequency_tx frequency in Hz (default: 8000) channel_count_tx channel number (1 or 2) (default: 1) buffer_ms time audio can be buffered without overflowing in milliseconds vendor_id Your vendor_id product_id Your product_id product_release Your product_release
Definition at line 132 of file USBAudio.cpp.
~USBAudio | ( | ) | [virtual] |
Destroy this object.
Any classes which inherit from this class must call deinit before this destructor runs.
Definition at line 192 of file USBAudio.cpp.
Member Function Documentation
void assert_locked | ( | ) | [protected, virtual, inherited] |
Assert that the current thread of execution holds the lock.
Definition at line 1737 of file USBDevice.cpp.
void attach | ( | mbed::Callback< void()> & | cb ) |
Attach a Callback to update the volume.
- Parameters:
-
cb Callback to attach
Definition at line 352 of file USBAudio.cpp.
void attach_rx | ( | mbed::Callback< void(AudioEvent)> & | cb ) |
attach a Callback to Rx Done
- Parameters:
-
cb Callback to attach
Definition at line 376 of file USBAudio.cpp.
void attach_tx | ( | mbed::Callback< void(AudioEvent)> & | cb ) |
attach a Callback to Tx Done
- Parameters:
-
cb Callback to attach
Definition at line 364 of file USBAudio.cpp.
virtual void callback_power | ( | bool | powered ) | [protected, virtual, inherited] |
Called by USBDevice layer on power state change.
- Parameters:
-
powered true if device is powered, false otherwise
Warning: Called in ISR context
Definition at line 342 of file USBDevice.h.
void callback_request | ( | const setup_packet_t * | setup ) | [protected, virtual] |
Called by USBDevice on Endpoint0 request.
This is used to handle extensions to standard requests and class specific requests. The function complete_request must be always be called in response to this callback.
Warning: Called in ISR context
Implements USBDevice.
Definition at line 398 of file USBAudio.cpp.
void callback_request_xfer_done | ( | const setup_packet_t * | setup, |
bool | aborted | ||
) | [protected, virtual] |
Called by USBDevice on data stage completion.
The function complete_request_xfer_done must be always be called in response to this callback.
- Parameters:
-
setup Setup packet of the current request aborted false if the operation was aborted, true otherwise
Warning: Called in ISR context
Implements USBDevice.
Definition at line 487 of file USBAudio.cpp.
virtual void callback_reset | ( | ) | [protected, virtual, inherited] |
Called by USBDevice layer on bus reset.
complete_reset must be called after the device is fully reset.
Warning: Called in ISR context
Definition at line 370 of file USBDevice.h.
virtual void callback_sof | ( | int | frame_number ) | [protected, virtual, inherited] |
Called by USBDevice layer on each new USB frame.
Callbacks are enabled and disabled by calling sof_enable and sof_disable.
- Parameters:
-
frame_number The current frame number
Warning: Called in ISR context
Definition at line 357 of file USBDevice.h.
void callback_state_change | ( | DeviceState | new_state ) | [protected, virtual] |
Called when USB changes state.
- Parameters:
-
new_state The new state of the USBDevice
Warning: Called in ISR context
Implements USBDevice.
Definition at line 388 of file USBAudio.cpp.
void complete_request | ( | RequestResult | result, |
uint8_t * | data = NULL , |
||
uint32_t | size = 0 |
||
) | [protected, inherited] |
Called to complete the setup stage of a callback request.
Possible options that can be passed as a result are:
- Receive - Start the data OUT phase of this control transfer
- Send - Start the data IN phase of this control transfer
- Success - Operation was a success so start the status phase
- Failure - Operation failed or is unsupported so send a stall
- PassThrough - Pass on the request for standard processing
- Parameters:
-
result The result of the setup phase. data Buffer to send or receive if the result is Send or Receive size Size to transfer if the result is Send or Receive
Definition at line 694 of file USBDevice.cpp.
void complete_request_xfer_done | ( | bool | success ) | [protected, inherited] |
Called to complete the data stage of a callback request.
- Parameters:
-
success true if the operation was successful, false otherwise
Definition at line 313 of file USBDevice.cpp.
void complete_set_configuration | ( | bool | success ) | [protected, inherited] |
Called to complete a set configuration command.
- Parameters:
-
success true if the configuration was set, false otherwise
Definition at line 386 of file USBDevice.cpp.
void complete_set_interface | ( | bool | success ) | [protected, inherited] |
Called to complete a set interface command.
- Parameters:
-
success true if the interface was set, false otherwise
Definition at line 466 of file USBDevice.cpp.
bool configured | ( | ) | [inherited] |
Check if the device is configured.
- Returns:
- true if configured, false otherwise
Definition at line 1043 of file USBDevice.cpp.
void connect | ( | ) |
void deinit | ( | ) | [inherited] |
Power down this instance.
Disable interrupts and stop sending events. This method can be used for temporary power-saving; This call can allow USB to be temporarily disabled to permit power saving. However, it is up to the user to make sure all the transfers have concluded (for example when USB power is lost). USBDevice::connect can be used to resume USB operation.
Definition at line 1030 of file USBDevice.cpp.
void disconnect | ( | void | ) |
Disconnect USBAudio.
This unblocks all calls to read_ready and write_ready.
Reimplemented from USBDevice.
Definition at line 215 of file USBAudio.cpp.
void endpoint_abort | ( | usb_ep_t | endpoint ) | [inherited] |
Abort the current transfer on this endpoint.
- Parameters:
-
endpoint endpoint with transfer to abort
- Note:
- This endpoint must already have been setup with endpoint_add
Definition at line 1396 of file USBDevice.cpp.
bool endpoint_add | ( | usb_ep_t | endpoint, |
uint32_t | max_packet, | ||
usb_ep_type_t | type, | ||
mbed::Callback< void()> | callback = NULL |
||
) | [inherited] |
Add an endpoint.
- Parameters:
-
endpoint Endpoint to enable max_packet Maximum size of a packet which can be sent or received on this endpoint type Endpoint type - USB_EP_TYPE_BULK, USB_EP_TYPE_INT or USB_EP_TYPE_ISO callback Method pointer to be called when a packet is transferred
- Returns:
- true if successful, false otherwise
Definition at line 1109 of file USBDevice.cpp.
bool endpoint_add | ( | usb_ep_t | endpoint, |
uint32_t | max_packet, | ||
usb_ep_type_t | type, | ||
void(T::*)() | callback | ||
) | [inherited] |
Add an endpoint.
- Parameters:
-
endpoint Endpoint to enable max_packet Maximum size of a packet which can be sent or received on this endpoint type Endpoint type - USB_EP_TYPE_BULK, USB_EP_TYPE_INT or USB_EP_TYPE_ISO callback Method pointer to be called when a packet is transferred
- Returns:
- true if successful, false otherwise
Definition at line 162 of file USBDevice.h.
uint32_t endpoint_max_packet_size | ( | usb_ep_t | endpoint ) | [inherited] |
Get the current maximum size for this endpoint.
Return the currently configured maximum packet size, wMaxPacketSize, for this endpoint.
- Note:
- This endpoint must already have been setup with endpoint_add
Definition at line 1380 of file USBDevice.cpp.
void endpoint_remove | ( | usb_ep_t | endpoint ) | [inherited] |
Remove an endpoint.
- Parameters:
-
endpoint Endpoint to disable
- Note:
- This endpoint must already have been setup with endpoint_add
Definition at line 1149 of file USBDevice.cpp.
void endpoint_remove_all | ( | ) | [inherited] |
Remove all non-zero endpoints.
Definition at line 1190 of file USBDevice.cpp.
void endpoint_stall | ( | usb_ep_t | endpoint ) | [inherited] |
Stall an endpoint.
If there is an ongoing transfer on this endpoint then it will be aborted.
- Parameters:
-
endpoint Endpoint to stall
- Note:
- You cannot stall endpoint 0 with this function
- This endpoint must already have been setup with endpoint_add
Definition at line 1204 of file USBDevice.cpp.
const usb_ep_table_t * endpoint_table | ( | ) | [protected, inherited] |
Get the endpoint table of this device.
Definition at line 1321 of file USBDevice.cpp.
void endpoint_unstall | ( | usb_ep_t | endpoint ) | [inherited] |
Un-stall an endpoint.
Un-stalling an endpoint resets data toggle back to DATA0. Additionally, if there is an ongoing transfer on this endpoint it will be aborted.
- Parameters:
-
endpoint Endpoint to un-stall
- Note:
- This endpoint must already have been setup with endpoint_add
Definition at line 1241 of file USBDevice.cpp.
uint8_t * find_descriptor | ( | uint8_t | descriptor_type, |
uint8_t | index = 0 |
||
) | [protected, inherited] |
Find a descriptor type inside the configuration descriptor.
- Parameters:
-
descriptor_type Type of descriptor to find index Configuration descriptor index ( 0 if only one configuration present )
- Returns:
- A descriptor of the given type or NULL if none were found
Definition at line 1278 of file USBDevice.cpp.
float get_volume | ( | ) |
void init | ( | ) | [inherited] |
Initialize this instance.
This function must be called before calling any other functions of this class, unless specifically
Definition at line 1017 of file USBDevice.cpp.
void lock | ( | void | ) | [protected, virtual, inherited] |
Acquire exclusive access to this instance USBDevice.
Definition at line 1714 of file USBDevice.cpp.
bool read | ( | uint8_t * | buf, |
uint32_t | size | ||
) |
Read audio data.
- Parameters:
-
buf pointer on a buffer which will be filled with audio data size size to read
- Returns:
- true if successful
Definition at line 229 of file USBAudio.cpp.
uint32_t read_finish | ( | usb_ep_t | endpoint ) | [inherited] |
Get the status of a read.
- Parameters:
-
endpoint endpoint to get the status of
- Returns:
- number of bytes read by this endpoint
Definition at line 1489 of file USBDevice.cpp.
void read_nb | ( | uint8_t * | buf, |
uint32_t | size, | ||
uint32_t * | actual | ||
) |
Nonblocking audio data read.
Read the available audio data.
- Parameters:
-
buf pointer on a buffer which will be filled with audio data size size to read actual size actually read
- Note:
- This function is safe to call from USBAudio callbacks.
Definition at line 243 of file USBAudio.cpp.
uint32_t read_overflows | ( | bool | clear = false ) |
Return the number read packets dropped due to overflow.
- Parameters:
-
clear Reset the overflow count back to 0
- Returns:
- Number of packets dropped due to overflow
Definition at line 256 of file USBAudio.cpp.
bool read_ready | ( | ) |
Check if the audio read channel is open.
- Returns:
- true if the audio read channel open, false otherwise
Definition at line 270 of file USBAudio.cpp.
bool read_start | ( | usb_ep_t | endpoint, |
uint8_t * | buffer, | ||
uint32_t | size | ||
) | [inherited] |
start a read on the given endpoint
Start a read on the given endpoint. The data buffer must remain unchanged until the transfer either completes or is aborted.
- Parameters:
-
endpoint endpoint to read data from buffer buffer to fill with read data size The size of data to read. This must be greater than or equal to the max packet size for this endpoint
- Returns:
- true if the read was completed, otherwise false
- Note:
- This endpoint must already have been setup with endpoint_add
Definition at line 1431 of file USBDevice.cpp.
void read_wait_ready | ( | ) |
Wait until the audio read channel is open.
Definition at line 281 of file USBAudio.cpp.
void sof_disable | ( | ) | [inherited] |
Disable the start of frame interrupt.
Stop calling USBDevice::callback_sof.
Definition at line 1100 of file USBDevice.cpp.
void sof_enable | ( | ) | [inherited] |
Enable the start of frame interrupt.
Call USBDevice::callback_sof on every frame.
Definition at line 1091 of file USBDevice.cpp.
void start_process | ( | ) | [protected, virtual, inherited] |
Callback called to indicate the USB processing needs to be done.
Implements USBPhyEvents.
Definition at line 1705 of file USBDevice.cpp.
void unlock | ( | void | ) | [protected, virtual, inherited] |
Release exclusive access to this instance USBDevice.
Definition at line 1721 of file USBDevice.cpp.
bool write | ( | uint8_t * | buf, |
uint32_t | size | ||
) |
Write audio data.
- Parameters:
-
buf pointer to audio data to write size size to write
- Returns:
- true if successful
Definition at line 286 of file USBAudio.cpp.
uint32_t write_finish | ( | usb_ep_t | endpoint ) | [inherited] |
Get the status of a write.
- Parameters:
-
endpoint endpoint to get the status of
- Returns:
- number of bytes sent by this endpoint
Definition at line 1583 of file USBDevice.cpp.
void write_nb | ( | uint8_t * | buf, |
uint32_t | size, | ||
uint32_t * | actual | ||
) |
Nonblocking audio data write.
Write the available audio data.
- Parameters:
-
buf pointer to audio data to write size size to write actual actual size written
- Note:
- This function is safe to call from USBAudio callbacks.
Definition at line 299 of file USBAudio.cpp.
bool write_ready | ( | ) |
Check if the audio write channel is open.
- Returns:
- true if the audio write channel open, false otherwise
Definition at line 325 of file USBAudio.cpp.
bool write_start | ( | usb_ep_t | endpoint, |
uint8_t * | buffer, | ||
uint32_t | size | ||
) | [inherited] |
Write a data to the given endpoint.
Write data to an endpoint. The data sent must remain unchanged until the transfer either completes or is aborted.
- Parameters:
-
endpoint endpoint to write data to buffer data to write size the size of data to send. This must be less than or equal to the max packet size of this endpoint
- Note:
- This endpoint must already have been setup with endpoint_add
Definition at line 1522 of file USBDevice.cpp.
uint32_t write_underflows | ( | bool | clear = false ) |
Return the number write packets not sent due to underflow.
- Parameters:
-
clear Reset the underflow count back to 0
- Returns:
- Number of packets that should have been sent but weren't due to overflow
Definition at line 312 of file USBAudio.cpp.
void write_wait_ready | ( | ) |
Wait until the audio write channel is open.
Definition at line 336 of file USBAudio.cpp.
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