nuttx-apps/system/composite

System / composite USB Composite

This logic adds a NSH command to control a USB composite device. The only supported devices in the composite are CDC/ACM serial and a USB mass storage device. Which devices are enclosed in a composite device is configured with an array of configuration-structs, handed over to the function composite_initialize().

Required overall configuration:

Enable the USB Support of your Hardware / Processor e.g. SAMV7_USBDEVHS=y

• CONFIG_USBDEV=y – USB device support.
• CONFIG_USBDEV_COMPOSITE=y – USB composite device support.
• CONFIG_COMPOSITE_IAD=y – Interface associate descriptor needed.
• CONFIG_CDCACM=y – USB CDC/ACM serial device support.
• CONFIG_CDCACM_COMPOSITE=y – USB CDC/ACM serial composite device support.

The interface-, string-descriptor- and endpoint-numbers are configured via the configuration-structs as noted above. The CDC/ACM serial device needs three endpoints; one interrupt-driven and two bulk endpoints.

• CONFIG_USBMSC=y – USB mass storage device support.
• CONFIG_USBMSC_COMPOSITE=y – USB mass storage composite device support.

Like the configuration for the CDC/ACM, the descriptor- and endpoint-numbers are configured via the configuration struct.

Depending on the configuration struct you need to configure different vendor- and product-IDs. Each VID/PID is unique to a device and thus to a dedicated configuration.

Linux tries to detect the device types and installs default drivers if the VID/PID pair is unknown.

Windows insists on a known and installed configuration. With an Atmel hardware and Atmel-Studio or the Atmel-USB-drivers installed, you can test your configuration with Atmel Example Vendor- and Product-IDs.

If you have a USBMSC and a CDC/ACM configured in your combo, then you can try to use

• VID = 0x03EB (ATMEL)
• PID = 0x2424 (ASF Example with MSC and CDC)

If for example you try to test a configuration with up to seven CDCs, then

• VID = 0x03EB (ATMEL)
• PID = 0x2426 (ASF Example with up to seven CDCs)

This add-on can be built as two NSH built-in commands:

• CONFIG_NSH_BUILTIN_APPS – if this option is selected: conn will connect the USB composite device; disconn will disconnect the USB composite device.

Configuration options unique to this add-on:

• CONFIG_SYSTEM_COMPOSITE_DEBUGMM – Enables some debug tests to check for memory usage and memory leaks.

If CONFIG_USBDEV_TRACE is enabled (or CONFIG_DEBUG_FEATURES and CONFIG_DEBUG_USB), then the add-on code will also manage the USB trace output. The amount of trace output can be controlled using:

• CONFIG_SYSTEM_COMPOSITE_TRACEINIT – Show initialization events.
• CONFIG_SYSTEM_COMPOSITE_TRACECLASS – Show class driver events.
• CONFIG_SYSTEM_COMPOSITE_TRACETRANSFERS – Show data transfer events.
• CONFIG_SYSTEM_COMPOSITE_TRACECONTROLLER – Show controller events.
• CONFIG_SYSTEM_COMPOSITE_TRACEINTERRUPTS – Show interrupt-related events.