1# ScsiPeripheral_IORequest 2 3 4## Overview 5 6Defines the read/write operation request. 7 8**Since**: 18 9 10**Related module**: [SCSI Peripheral DDK](_s_c_s_i.md) 11 12**Header file**: [scsi_peripheral_types.h](scsi__peripheral__types_8h.md) 13 14 15## Summary 16 17 18### Member Variables 19 20| Name| Description| 21| -------- | -------- | 22| uint32_t [lbAddress](#lbaddress) | Start address of a logical block.| 23| uint16_t [transferLength](#transferlength) | Number of consecutive logical blocks to be operated.| 24| uint8_t [control](#control) | **Control** field used to specify control information.| 25| uint8_t [byte1](#byte1) | First byte of the CDB.| 26| uint8_t [byte6](#byte6) | Sixth byte of the CDB.| 27| [ScsiPeripheral_DeviceMemMap](_scsi_peripheral___device_mem_map.md) \* [data](#data) | Buffer for data transmission.| 28| uint32_t [timeout](#timeout) | Timeout duration, in ms.| 29 30 31## Member Variable Description 32 33 34### byte1 35 36``` 37uint8_t ScsiPeripheral_IORequest::byte1 38``` 39 40**Description** 41 42First byte of the CDB. 43 44 45### byte6 46 47``` 48uint8_t ScsiPeripheral_IORequest::byte6 49``` 50 51**Description** 52 53Sixth byte of the CDB. 54 55 56### control 57 58``` 59uint8_t ScsiPeripheral_IORequest::control 60``` 61 62**Description** 63 64**Control** field used to specify control information. 65 66 67### data 68 69``` 70ScsiPeripheral_DeviceMemMap* ScsiPeripheral_IORequest::data 71``` 72 73**Description** 74 75Buffer for data transmission. 76 77 78### lbAddress 79 80``` 81uint32_t ScsiPeripheral_IORequest::lbAddress 82``` 83 84**Description** 85 86Start address of a logical block. 87 88 89### timeout 90 91``` 92uint32_t ScsiPeripheral_IORequest::timeout 93``` 94 95**Description** 96 97Timeout duration, in ms. 98 99 100### transferLength 101 102``` 103uint16_t ScsiPeripheral_IORequest::transferLength 104``` 105 106**Description** 107 108Number of consecutive logical blocks to be operated. 109