Fujitsu MBC2036RC, MBC2073RC, MBA3300RC, MBA3147RC, MBA3073RC specifications TOO Much Write Data

Models: MBA3300RC MBA3147RC MBA3073RC MBC2073RC MBC2036RC

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1.6 Transport layer

DATA OFFSET field

The DATA OFFSET field is used to check whether frames are being transferred in the correct order. When the drive receives a frame with an offset value that the drive does not expect, the drive sends the ACK primitive and CREDIT_BLOCKED primitive, and discards the DATA frame. At this time, after temporarily closing the connection, the drive re-opens a connection and sends the SENSE DATA for DATA OFFSET ERROR.

Received data length

When a data item with a data length exceeding the value specified in the WRITE DATA LENGTH field of the XFER_RDY frame is received, the drive sends the ACK primitive and CREDIT_BLOCKED primitive, and discards the DATA frame. At this time, after temporarily closing the connection, the drive re-opens a connection and sends the SENSE DATA for

TOO MUCH WRITE DATA.

Meanwhile, when a drive sends a read DATA frame, the following values are set:

HASHED DESTINATION SAS ADDRESS field

The hashed SAS address of the COMMAND frame is set.

HASHED SOURCE SAS ADDRESS field The hashed SAS address of the drive is set.

NUMBER OF FILL BYTES field

If the transferred bytes in the last DATA frame for the command are not aligned on a four byte boundary, the number of the extra bytes (4 - the remainder of [the number of all transferred bytes/4] bytes) is set in this field.

TAG field

The tag value of the COMMAND frame is set.

TARGET PORT TRANSFER TAG field Set to 0xFFFF by the drive.

DATA OFFSET field

For the first DATA frame of the command, this field is set to zero. For the second DATA frame, the DATA OFFSET field is increased by the number of the transferred bytes of the first DATA frame.

Number of transferred bytes

When the number of bytes to be transferred is greater than or equal to 1024 bytes, this field is set to 1024. When the number of bytes to be transferred is less than 1024 bytes, this field is set to that number of bytes.

C141-C013

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Fujitsu MBC2036RC, MBC2073RC, MBA3300RC, MBA3147RC, MBA3073RC specifications TOO Much Write Data