Western Digital T13/2132-D manual Formatted Protocol Specific Data

June 23, 2010 T13/2132-D Revision 3

This PSS shall add transport specific information (e.g., header information and CRC) and modify the CDB where necessary with bus specific information. If the secondary bus is a hot-plug bus such as 1394 or USB, the PSS shall insert device addresses or EUI-64 as necessary. In the event that a device address changes due to a bus reset or re-enumeration, the PSS shall connect with the device without generating an error.

8.27.2.2 Formatted Protocol Specific Data

Table 31 defines the format of the data passed in ES:SI (see 8.27.1) to INT 13h FN 50h.

			Table 31 — Formatted Protocol Specific Data
Offset	Type		Description
0	Word	Packet length in bytes including this word
2	Byte	Information flags
		Bit	Description
		7:6	Data direction.
			00 = No data exchanged with device (command only)
			01 = Receive data from device
			10 = Send data to device
			11 = Reset Interface.
		5:0	Reserved
3	Byte	Bytes in command packet, or zero if no command is to be sent.
4	DWord	Pointer to command packet. This field follows the seg:offset address format. This field is
		ignored if offset 3 is zero.
8	DWord	Number of bytes to transfer following command complete. Shall be a multiple of the sector
		size of the media, as returned by Function 48h. If the data direction bits in the flags register
		do not indicate a send or receive data command, then this field shall be ignored. Otherwise,
		if this value shall be zero, then a zero byte transfer shall occur.
10h	DWord	Pointer to the start of the data stream to transfer. This field follows the seg:offset address
		format.
14	Word	Access timeout. Maximum time in milliseconds to wait for command start. Command start
		includes sending the command to the devices and waiting for the first data byte to transfer.
		If this field contains the value of 0000h, an 80h error (see table 32) shall result.
16	Word	Sector timeout increment. The PSS shall divide the amount of data transferred by the
		sector size, round up, multiply by this value, and add to the Access Timeout (offset 14), the
		maximum result is limited to FFFFh. This shall be the total timeout for the specified CDB.
		This value shall be ignored for command-only and bus-reset calls.

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