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Identification card systems — Man-machine interface
Part 4 : Coding of user requirements for people with special needs

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5 User interface data elements

5.1 General remarks

For each data element, the following descriptors may be present :

Absence of a data object in the card indicates that no special requirements apply in the area concerned.

It is essential that information is only stored on a card with the consent of the user.

The interface device should not retain the data elements stored on the card.

5.2 Principles

The following principles apply to the identification of user preference data elements within this standard :

5.3 Data object structure

The following data object structures are supported :

primitive data object

T

L

V

where T = Tag, L = Length, V = Value

constructed data object

T

L

T1

L1

V1

T2

L2

V2

...

Tn

Ln

Vn

T = Tag of constructed data object.
L = Length of the string (template) T1 to Vn^.
T1 = Tag of a data object.
L1 = Length of V1^.
V1 = Value.

5.3.1 Structure of the tag

The tag consists of one or two bytes. The coding of these bytes shall be consistent with the basic encoding rules of ASN.1 as defined in ISO/IEC 8825. Table 1 defines the first byte.

Table 1 - Structure of the first byte of the tag

b8	b7	b6	b5	b4	b3	b2	b1	Meaning
0	0	-	-	-	-	-	-	Not defined in this standard
0	1	-	-	-	-	-	-	Defined in this standard Application class, unambiguous identification
1	0	-	-	-	-	-	-	Defined in this document and only to be used within a template
1	1	-	-	-	-	-	-	Not defined in this document. Reserved for private use
-	-	0	-	-	-	-	-	Primitive data object
-	-	1	-	-	-	-	-	Constructed data object
-	-	-	1	1	1	1	1	Tag number contained in the next byte - range 31..127
-	-	-	x	x	x	x	x	Tag number - range 0 - 30 Not all equal to 1

The coding of the second byte of the tag, when present, is :

b8=0

b7to b1=binary value of the tag number in the range 31..127.

5.3.2 Structure of the length

All lengths are expressed in bytes.

The length consists of one or more bytes. The coding of these bytes shall be consistent with the basic encoding rules of ASN.1 and shall be as defined in Table 2.

Table 2 - Coding of the length value

Range	Number of bytes	1st byte	2nd byte	3rd byte
0..127	1	binary value	none	none
0..255	2	‘81’	binary value	none
0..65,535	3	‘82’	binary ms byte	value ls byte

5.4 List of data elements

This subclause defines data elements which may be present within an integrated circuit(s) card to indicate user interface preferences, but always recognising the terminal may not be able to provide the precise options requested.

5.4.1 Symbols

Purpose:	To indicate the preferred method of presentation of visual information, either via text, symbols, Braille or a combination of both.
Format:	1 byte.
Content:	The content of this field is in accordance with Table 3.

Table 3 - Content of the symbols data element

b8	b7	b6	b5	b4	b3	b2	b1	Meaning
-	-	-	-	-	-	-	1	Text required
-	-	-	-	-	-	1	-	Symbols required
-	-	-	-	-	1	-	-	Sign language required
-	-	-	-	1	-	-	-	Braille output required
x	x	x	x	-	-	-	-	Reserved for future use. All bits set to zero

Remarks - This data element is addressed through the use of tag number ‘DF 50’.

5.4.2 Character size

Purpose:	This data element enables the preferred size of any text information to be provided to the terminal device.
Format:	1 byte.
Content:	The height of characters in millimetres. The width of characters shall be in proportion to the specified height for the particular font being displayed.

Remark- This data element is addressed through the use of tag number ‘DF 51’.

5.4.3 Screen colour

Purpose:	To indicate preferred colours for the presentation of visual information.
Format:	1 byte.
Content:	The coding of the screen colour byte shall be in accordance with Table 4.

Table 4 - Content of the screen colours data element

b8	b7	b6	b5	b4	b3	b2	b1	Meaning
-	-	-	-	-	x	x	x	Preferred colour for text according to the values specified below
-	-	x	x	x	-	-	-	Preferred background colour according to the values specified below
x	x	-	-	-	-	-	-	Reserved for future use. All bits set to zero

Colour coding scheme for text and background :

000 : white
001 : red
010 : orange
011 : yellow
100 : green
101 : blue
110 : purple
111 : black

RemarkThis data element is addressed through the use of tag number ‘DF 52’.

5.4.4 Colour avoidance

Purpose:	To indicate specific colours or combination of colours to be avoided when displaying visual information to the user.
Format:	1 byte.
Content:	The coding of the colour avoidance byte shall be in accordance with Table 5.

Table 5 - Content of the colour avoidance data element

b8	b7	b6	b5	b4	b3	b2	b1	Meaning
-	-	-	-	-	-	-	1	Avoid display of information in red
-	-	-	-	-	-	1	-	Avoid red/green colour combination
-	-	-	-	-	1	-	-	Avoid blue/yellow colour combination
-	-	-	-	1	-	-	-	Maximum contrast monochrome
x	x	x	x	-	-	-	-	Reserved for future use. All bits set to zero

RemarkThis data element is addressed through the use of tag number ‘DF 53’.

5.4.5 Position of screen

Purpose:	To enable automatic height positioning of a screen to assist users in the reading of information.
Format:	1 byte coded as two BCD digits.
Content:	The value of this element denotes the desired height of the centre of a visual display in decimetres relative to the ground or floor level.

Remark- This data element is addressed through the use of tag number ‘DF 54’.

5.4.6 Voice output

Purpose:	To indicate the preferred device for the voice related information.
Format:	1 byte binary.
Content:	The coding of the voice output byte shall be in accordance with Table 6.

Table 6 - Content of the voice output data element

b8	b7	b6	b5	b4	b3	b2	b1	Meaning
-	-	-	-	-	-	-	1	Loudspeaker output required
-	-	-	-	-	-	1	-	Headset output required
-	-	-	-	-	1	-	-	Hearing aid - magnetic inductive coupling required
x	x	x	x	x	-	-	-	Reserved for future use. All bits set to zero

RemarkThis data element is addressed through the use of tag number ‘DF 55’.

5.4.7 Sound amplification

Purpose:	To enable sound amplification to be performed by the terminal for voice or other output information.
Format:	1 byte binary.
Content:	The coding of the sound amplification byte shall be in accordance with Table 7.

Table 7 - Content of the sound amplification data element

b8	b7	b6	b5	b4	b3	b2	b1	Meaning
-	x	x	x	x	x	x	x	Offset amount in dBA from the terminal’s normal sound level
0	-	-	-	-	-	-	-	Positive value denoted in bits b1 to b7
1	-	-	-	-	-	-	-	Negative value denoted in bits b1 to b7

Remark- This data element is addressed through the use of tag number ‘DF 56’.

5.4.8 High frequency amplification

Purpose:	To enable sound amplification to be performed by the terminal for high frequency voice or other output information.
Format:	1 byte binary.
Content:	The coding of the high frequency amplification byte shall be in accordance with Table 8.

Table 8 - Content of the high frequency amplification data element

b8	b7	b6	b5	b4	b3	b2	b1	Meaning
-	x	x	x	x	x	x	x	Offset amount in dBA from the terminal’s normal sound level
0	-	-	-	-	-	-	-	Positive value denoted in bits b1 to b7
1	-	-	-	-	-	-	-	Negative value denoted in bits b1 to b7

Remark- This data element is addressed through the use of tag number ‘DF 57’.

5.4.9 Low frequency amplification

Purpose:	To enable sound amplification to be performed by the terminal for low frequency voice or other output information.
Format:	1 byte binary.
Content:	The coding of the low frequency amplification byte shall be in accordance with Table 9.

Table 9 - Content of the low frequency amplification data element

b8	b7	b6	b5	b4	b3	b2	b1	Meaning
-	x	x	x	x	x	x	x	Offset amount in dBA from the terminal’s normal sound level
0	-	-	-	-	-	-	-	Positive value denoted in bits b1 to b7
1	-	-	-	-	-	-	-	Negative value denoted in bits b1 to b7

Remark- This data element is addressed through the use of tag number ‘DF 58’.

5.4.10 Input requirements

Purpose:	To indicate the preferred method for input of data into the terminal.
Format:	1 byte binary.
Content:	The coding of the input requirements byte shall be in accordance with Table 10.

Table 10 - Content of the input requirements data element

b8	b7	b6	b5	b4	b3	b2	b1	Meaning
-	-	-	-	-	-	-	1	Voice input required
-	-	-	-	-	-	1	-	Keyboard input required
-	-	-	-	-	1	-	-	PIN pad top row denotes the digits 1,2,3
-	-	-	-	1	-	-	-	PIN pad top row denotes the digits 7,8,9
x	x	x	x	-	-	-	-	Reserved for future use. All bits set to zero

Remark- This data element is addressed through the use of tag number ‘DF 59’.

5.4.11 Touch screen

Purpose:	To indicate the preferred layout and icon characteristics for a touch screen input device.
Format:	1 byte binary.
Content:	The coding of the touch screen byte shall be in accordance with Table 11.

Table 11 - Content of the touch screen data element

b8	b7	b6	b5	b4	b3	b2	b1	Meaning
-	-	-	-	-	-	0	1	Large button size required
-	-	-	-	-	-	1	0	Very large button size required
-	-	-	-	-	0	-	-	Finger entering touch-sensitive area
-	-	-	-	-	1	-	-	Finger exiting touch-sensitive area
x	x	x	x	x	-	-	-	Reserved for future use. All bits set to zero

Remark - In the above Table, "button" refers to the target area to be touched on the screen to activate the input.

This data element is addressed through the use of tag number ‘DF 5A’.

5.4.12 Position of input device

Purpose:	To enable automatic height positioning of a data input device to assist users in the entry of information.
Format:	1 byte coded as two BCD digits.
Content:	The value of this element denotes the desired height of the centre of the input device in decimetres from ground level.

Remarks- This data element is addressed through the use of tag number ‘DF 5B’.

5.4.13 Time-outs

Purpose:	To indicate a requirement for additional time beyond the normal time-out to complete user input processes, thus reducing the potential for errors caused by device time-outs.
Format:	2 digits numeric.
Content:	The number of seconds of time required before a time-out or a series of time-outs shall come into force.

RemarksThis data element is addressed through the use of tag number ‘DF 5C’.

5.4.14 Language

Purpose:	To indicate up to 4 preferred languages in order of user preference.
Format:	2 alphabetic characters per language.
Content:	This element is coded in accordance with ISO 639.

Remarks- This data element is addressed through the use of tag number ‘5F 2D’ as defined in EN ISO/IEC 7816-6.

5.4.15 Interface complexity level

Purpose:	To indicate the preferred level of complexity for dialogue or text presented to the user.
Format:	1 byte binary.
Content:	The coding of the interface complexity level byte shall be in accordance with Table 12.

Table 12 - Content of the interface complexity level data element

b8	b7	b6	b5	b4	b3	b2	b1	Meaning
-	-	-	-	-	-	0	1	Simplified dialogue level required
-	-	-	-	-	-	1	0	Very simplified dialogue required
-	-	-	-	-	-	1	1	Reserved for future use
-	-	-	-	0	1	-	-	Simplified text required
-	-	-	-	1	0	-	-	Very simplified text required
-	-	-	-	1	1	-	-	Reserved for future use
-	-	0	1	-	-	-	-	Low text density required
-	-	1	0	-	-	-	-	Very low text density required
-	-	1	1	-	-	-	-	Reserved for future use
x	x	-	-	-	-	-	-	Reserved for future use. Both bits set to zero

Remark- This data element is addressed through the use of tag number ‘DF 5D’.

5.4.16 Application independent requirements

Purpose:	To indicate the set of user requirements independent of the application being implemented.
Format:	n bytes binary (n is dependent on the number of requirements specified).
Content:	A constructed data element comprising the individual interface requirements.

Remarks- This data element is addressed through the use of tag number ‘FF 60’. This data element may be retrieved following application selection using the GET DATA command (in accordance with EN ISO/IEC 7816-4) referencing the tag number within the content of the command message.

5.4.17 Application specific requirements

Purpose:	To indicate the set of user requirements which are specific to the application being implemented.
Format:	n bytes binary (n is dependent on the number of requirements specified).
Content:	A constructed data element comprising the individual interface requirements.

Remarks- This data element is addressed through the use of tag number ‘FF 61’. This data element may be retrieved using the GET DATA command (in accordance with EN ISO/IEC 7816-4) referencing the tag number within the content of the command message. This data element may be replicated in the event of a multi-application card, particularly where the terminal is required to perform different actions on the same data element.

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