This function causes an SCB or a chain of SCBs to be sent to the adapter.

┌─────────────────────────────────────────────┬───────────────┐
│Field Name                                   │Length         │
├─────────────────────────────────────────────┼───────────────┤
│Device Handle                                │WORD           │
├─────────────────────────────────────────────┼───────────────┤
│Sense Data Size                              │WORD           │
├─────────────────────────────────────────────┼───────────────┤
│Physical Pointer to SCB                      │DWORD          │
├─────────────────────────────────────────────┼───────────────┤
│Logical Pointer to SCB Chain Header          │DWORD          │
├─────────────────────────────────────────────┼───────────────┤
│Flags                                        │BYTE           │
└─────────────────────────────────────────────┴───────────────┘

──────────────────────────────────────────────────────────────────────────

FUNCTION CATEGORY : 80h
FUNCTION CODE     : 52h

──────────────────────────────────────────────────────────────────────────

This function requires a device handle to be passed in the request. The device must be allocated by the device-class driver before calling this function. The function category and function code are to be set up as shown above.

Flags

Bit 0 =

0 Normal Length SCB
1 Long SCB

A normal length SCB is used to send generic SCSI commands to a device. The long SCB is used to send a vendor-unique SCSI command embedded in the SCB.

Data Buffer

If an error occurs, the data buffer might contain sense data; the return code indicates whether the sense data is valid. A termination status block also might be returned.

SCB Chain Header

          +00h  ┌────────────────────────────┐                │   Reserved                 │
          +02h  ├────────────────────────────┤
                │   Logical Pointer to next  │
                ├─  SCB Chain Header        ─┤
                │                            │
          +06h  ├────────────────────────────┤
                │   Reserved                 │
          +08h  ├────────────────────────────┤
                │   Reserved                 │
          +0Ah  ├────────────────────────────┤
                │   Logical Pointer to TSB   │
                ├─                          ─┤
                │                            │
          +0Eh  ├────────────────────────────┤
                │   Reserved                 │
          +10h  ├────────────────────────────┤
                │                            │
                │                            │
                │            SCB             │
                │                            │
                │        Immediately         │
                │                            │
                │           Follows          │
                │                            │
                │             the            │
                │                            │
                │            Chain           │
                │                            │
                │           Header           │
                │                            │
                │                            │
                └────────────────────────────┘

See Subsystem Control Blocks for a description of the SCB architecture.

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