HP Q153090901 manual 144

Data returned

The returned Parameter Data contains a 4-byte header followed by one or more command descriptors:

	7	6	5		4	3	2	1	0
0	(MSB)			Command Data Length
3									(LSB)

Command Data Length The amount of Parameter Data available for return minus the size of the header.

Each command descriptor contains either a supported Operation Code or an Operation Code/ Service Action combination. The format of each descriptor is as follows:

	7	6	5		4		3	2	1	0
0					Operation	Code
1					Reserved (0)
2	(MSB)				Service Action
3										(LSB)
4					Reserved (0)
5				Reserved (0)						ServActv
6	(MSB)				CDB Length
7										(LSB)
Operation Code		The operation code of the supported command.
Service Action		A supported service action of the operation code. If no service actions are supported
		this field will be 00h.
ServActv		0 No service actions are supported and the Service Action field should be
		ignored.
		1 This operation code supports service actions and the Service Action field
		contains a valid service actions.
CDB Length		The length of the CDB for this operation code or operation code/service action
		command.

144 Commands