The mode parameter list, including the mode parameter header and mode block descriptor, is defined in 8.3.3.
The medium-type code field is contained in the mode parameter header (see 8.3.3). This field is reserved for scanners devices.
The device specific parameter field is contained in the mode parameter header (see 8.3.3). This field is reserved for scanner devices.
The density code field is contained in the mode parameter block descriptor (see table 8.3.3). This field is reserved for scanner devices.
The mode page codes for scanner devices are defined in table 296.
Table 296 - Mode page codes
=============================================================================== | Page code | Description | Subclause | |-----------------------------------------------------------------------------| | 0Ah | Control mode page | 8.3.3.1 | | 02h | Disconnect-reconnect page | 8.3.3.2 | | 03h | Measurement units page | 15.3.3.1 | | 09h | Peripheral device page | 8.3.3.3 | | 01h | Reserved | | | 03h - 08h | Reserved | | | 0Bh - 1Fh | Reserved | | | 00h | Vendor-specific (does not require page format) | | | 20h - 3Eh | Vendor-specific (page format required) | | | 3Fh | Return all pages | | | | (valid only for the MODE SENSE command) | | ===============================================================================15.3.3.1 Measurement units page
The measurement units page (see table 297) specifies the units of measurement used for calculating the displacement of window and for positioning an object.
The measurement units are independent of the horizontal and vertical scan resolutions.
Table 297 - Measurement units page
=============================================================================== | Bit| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |Byte | | | | | | | | | |=============================================================================| | 0 | PS |Reserved| Page code (03h) | |-----------------------------------------------------------------------------| | 1 | Parameter length (06h) | |-----------------------------------------------------------------------------| | 2 | Basic measurement unit | |-----------------------------------------------------------------------------| | 3 | Reserved | |-----------------------------------------------------------------------------| | 4 | (MSB) | |--------- Measurement unit divisor ---| | 5 | (LSB) | |-----------------------------------------------------------------------------| | 6 | Reserved | |-----------------------------------------------------------------------------| | 7 | Reserved | ===============================================================================The parameters savable (PS) bit is only used with the MODE SENSE command. This bit is reserved for the MODE SELECT command. A PS bit of one indicates that the target is capable of saving the page in a non-volatile vendor-specific location.
The basic measurement unit field is defined in table 298. Targets shall use inches as the default basic measurement unit.
Table 298 - Basic measurement units
=============================== | Code | Description | |-----------------------------| | 00h | Inch | | 01h | Millimetre | | 02h | Point | | 03h - FFh | Reserved | ===============================The measurement unit divisor specifies the number of units needed to equal one basic measurement unit. Targets shall use 1 200 as the default measurement unit divisor. If a value of zero is specified the target shall return CHECK CONDITION status and set the sense key to ILLEGAL REQUEST.
( A target that does not implement this page or only supports default values uses twelve hundredths (1/1200) of an inch as the unit of measure. )