1# ScsiPeripheral_IORequest 2<!--Kit: Driver Development Kit--> 3<!--Subsystem: Driver--> 4<!--Owner: @lixinsheng2--> 5<!--Designer: @w00373942--> 6<!--Tester: @dong-dongzhen--> 7<!--Adviser: @w_Machine_cc--> 8 9## Overview 10 11Defines the read/write operation request. 12 13**Since**: 18 14 15**Related module**: [SCSIPeripheralDDK](capi-scsiperipheralddk.md) 16 17**Header file**: [scsi_peripheral_types.h](capi-scsi-peripheral-types-h.md) 18 19## Summary 20 21### Member Variables 22 23| Name| Description| 24| -- | -- | 25| uint32_t lbAddress | Start address of a logical block.| 26| uint16_t transferLength | Number of consecutive logical blocks to be operated.| 27| uint8_t control | **Control** field used to specify control information.| 28| uint8_t byte1 | First byte of the CDB.| 29| uint8_t byte6 | Sixth byte of the CDB.| 30| ScsiPeripheral_DeviceMemMap* data | Buffer for data transmission.| 31| uint32_t timeout | Timeout duration, in ms.| 32