1# Usb_DeviceArray 2 3 4## Overview 5 6Defines the device ID list, which is used to store the device IDs and device quantity obtained using [OH_Usb_GetDevices()](_usb_ddk.md#oh_usb_getdevices16). 7 8**Since** 9 1016 11 12**Related Modules** 13 14[USB DDK](_usb_ddk.md) 15 16 17## Summary 18 19 20### Member Variables 21 22| Name| Description| 23| -------- | -------- | 24| [deviceIds](#deviceids) | Start address of the device ID array.| 25| [num](#num) | Device quantity.| 26 27## Member Variable Description 28 29 30### deviceIds 31 32 33``` 34uint64_t* Usb_DeviceArray::deviceIds 35``` 36 37**Description** 38 39Defines the start address of the device ID array. The number of device IDs cannot exceed 128. 40### num 41 42 43``` 44uint32_t Usb_DeviceArray::num 45``` 46 47**Description** 48 49Defines the device quantity. Device IDs are obtained by traversing **deviceIds** based on the value of this parameter. If the value is **0**, there is no USB device. 50