ITRM20120038A1 - INTERACTION METHOD WITH TACTILE SCREEN DEVICES - Google Patents

Description

DESCRIPTION of the invention having as TITLE:

â € œMETHOD OF INTERACTION WITH TOUCH SCREEN DEVICESâ €,

DETAILED DESCRIPTION

The invention relates to an interaction method that allows a subject to use a device equipped with a touch screen through the thumb while supporting the device with one or both hands, specifically the invention allows the replacement of traditional interfaces for the character entry for devices equipped with a touch screen as it is more efficient and more comfortable than existing interfaces when the device is supported with one or both hands. The interaction managed according to the method described allows to obtain greater practicality and efficiency with respect to the existing solutions and the solutions described in the literature, in particular when the user supports the device with one or both hands.

The invention applies to devices equipped with a touch screen that can be used through gestures performed near or in contact with the screen, in particular it is suitable for the case of handheld devices, tablet computers (so-called tablets in English), mobile phones (so-called smartphones in English), and similar equipped with a touch screen. Observations show that for many users of devices equipped with a touch screen, it is considered comfortable to interact (in the sense of giving commands or in any case using the device) preferably using the tactile area easily accessible through the extension of the fingers (in particular, of the thumb) starting from the condition in which the device is held with one hand or with both hands.

On the other hand, raising the whole hand and engaging it to perform gestures on the screen (the so-called gestures in English) for the purpose of giving commands may not be preferable or desired in certain circumstances or, in any case, it may not be the action is more efficient than the possibility of issuing the same command by continuing to hold the device, but simply by moving the thumb over the touch screen.

The finding originates from the following findings:

1) Observations show that Users find it convenient to use the Device by holding it with one or both hands.

2) Observations show that Users who support the Device with one or both hands spend most of their time keeping their thumb on the side of the touch screen, with part of the basal phalanx along an area of the edge (lateral or lower ) next to a lower end of the Device and with the end of the same thumb facing the top of the Device.

3) The considerations referred to in the previous points are probably inevitable as there are factors that push the user to assume a comfortable position (i.e. a position that allows a reduced expenditure of energy for the body) for use of the device; the factors mentioned include the shape and weight that generally characterize the Device, and the need for the User to have the Device within a distance that allows viewing of the screen and possibly giving commands.

4) Due to the relatively small dimensions that characterize the screens of the Devices, and to the generally frontal position assumed by the User during use (both for the needs of viewing the screen and for the need to interact with the Device ), the User who wishes to grip the Device spontaneously arranges his hand (or hands) in order to leave the most important area clear and to be able to observe an area as large as the screen, and the way in which the User holding the Device is once again the same as indicated in the previous points.

For the purposes of this document, the following terms are defined: a) Device: a device equipped with a touch screen that can be used through gestures that involve contact with the screen. b) User: a person who interacts with the Device or who in any case uses the Device.

c) Gesture: a movement made by the User on the touch screen of the Device in order to interact or in any case to use the Device. Gestures (so-called gestures in English) can be performed by articulating the fingers with simple or complex movements. For the purposes of the invention, the gestures that the User can perform by means of the thumb of the hand holding the

Device, in particular the contact of the thumb on a surface of the touch screen and movements performed with the thumb on the surface of the touch screen.

d) Symbol: letter of the alphabet, or number, or element of punctuation, or other character coming from a set that the Device is able to manage (so-called font in English). Each symbol that can be used through the invention is combined with a graphic representation that allows the User to identify and select the symbol itself and a numerical code. By way of example but not limited to, the symbols can be identified by the set {A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q , R, S, T, U, Î1⁄2, W, X, Y, Z} joined to the set {a, b, c, d, e, f, g, h, i, j, k, I, m, n, o, p, q, r, s, t, u, v, w, x, y, z} joined to the set {à €, È, ì, à ', à ™} joined to the set ™ together {Ã, à ̈, à ̈, ì, ò, ù} U {0, 1, 2, 3, 4, 5, 6, 7, 8, 9} joined to the whole {!,?, \ ", €, $, £, &, \, /,%, (,), [,],, -, *, =, <>, |, <Î ›>, 9,

} joined to the set consisting of the carriage return character, the forward tabulation character, the backward tabulation character, the comma, the space character, the opening brace, the closing brace. It is explicitly noted that in the extensive representation of the indicated sets, the curly brackets have been used to delimit a set of elements, and the comma has been used to indicate the separation between these elements. The code associated with each symbol is chosen in accordance with international standards for character encoding, thus the invention can operate on various types of systems and equipment, including systems and equipment specialized for specific languages and cultures.

e) Button: area sensitive to User gestures, used to present and allow the selection of a Symbol, an operating condition or an interaction command. The button is displayed on the screen of the Device, therefore the presentation and behavior of the button are to be understood in a logical and not a physical sense.

f) Representative point of the contact area: single point used to represent the contact area. If the device is not able to indicate this point, it is deduced from the analysis of the set of points that make up the contact area and is evaluated as a barycentral point, i.e. the horizontal and verticals of the representative point of the contact area are determined, respectively, as the average of the relative coordinates (horizontal or vertical, according to the case) of the points that make up the contact area, with rounding to the nearest whole value.

With reference to the natural disposition of the hand or hands used by the User to support the Device, the invention, unlike traditional interfaces for entering characters, allows to fully exploit the possibilities of interaction through the thumb. Figure 1 shows a representation of the touch screen and a representation of the traditional interface for entering characters. The distinct part at number 1 of figure 1 represents the touch screen of the device. The distinct part at number 2 of figure 1 represents a generic traditional interface that the User can use to enter characters into the Device.

Figure 1 is intended as a mere example and is not exhaustive. In particular, although in figure 1 (as well as in subsequent figures) the touch screen is represented in a rectangular shape and having chosen a larger edge for the base, these characteristics (like other characteristics such as dimensions and proportions) are not of interest and are not relevant for the purposes of applying the invention. Similarly, the representation of the traditional interface for entering characters (part number 2 of figure 1) is purely illustrative, as it is not possible to summarize the various types of construction using a single representation; in particular, the traditional interface for entering characters is not necessarily a single body, they are described in the literature and there are real examples of subdivision of the same interface on both sides.

Figure 2 shows a typical natural arrangement of the thumbs on the Touchscreen of the Device, when the Device is held by one hand or both.

The distinct part at number 3 of figure 2 represents the body of the device.

The distinct part at number 4 of figure 2 represents the touch screen of the device.

The thumb of the User's right hand is represented at number 5 in figure 2, while the Device is held (the remaining part of the hand is not shown in the figure).

The thumb of the User's left hand is represented at number 6 in figure 2, while the Device is held (the remaining part of the hand is not shown in the figure).

The distinct part at number 7 of figure 3 represents in a purely schematic way the interface associated with the invention (this interface is detailed in this document) for the case of a single-sided configuration suitable for a right-handed user.

A purely specular version of figure 7, with respect to the vertical axis of the drawing, allows left-handed Users to be able to effectively use the Device.

The distinct part at number 8 of figure 4 represents in a purely schematic way the left portion of the interface associated with the invention (this interface is detailed in this document) for the case of bilateral configuration and right-handed user.

With reference to the method of entering characters, unlike traditional interfaces for entering characters, the invention does not require movement of the hand, or movements of several fingers of a hand, and allows the user to enter characters using only the thumb of one hand. one hand while the Device is held with one hand or both.

With reference to the geometric characteristics, unlike the traditional interfaces for entering characters, the interface of the invention is characterized by an arrangement of the parts suitable for the interaction performed by the User exclusively by means of the thumb of the hand that holds the device .

With reference to the dimensions, unlike the traditional interfaces for entering characters, the interface of the invention develops along a limited surface consequently the User considers a single area on which to focus his gaze and where it is better to focus his attention. .

With reference to the symbols that can be selected, the interface of the invention can adapt its content, in particular the symbols displayed, in accordance with the requirements of use.

With reference to the set of symbols presented to the User at a given time and among which the User can choose, it corresponds to a selection suitable for frequent use scenarios.

The invention makes it possible to support specific interaction activities, in particular the activity aimed at the input of characters, through a system that can be easily reached by the thumb of the hand or the hands supporting the device.

Typically to allow the entry of text and numbers, a Touchscreen Device temporarily displays a virtual keyboard or other visual representation of keys on its screen. The consistency and characteristics of this virtual keyboard can possibly be specialized according to the conditions of use. Although it is not an exhaustive case, and similarly to what happens with traditional interfaces (including the so-called IMEs), the consistency and characteristics of the interface can be adapted based on any attribute corresponding to the intended use associated with the editable element that determined the activation of the interface. For this purpose, a table (indicated as the operating mode table) is specified as the configuration parameter, the columns of which contain the following data:

1) Numerical value corresponding to the intended use of the interface;

2) Set containing the enabling status of each sensitive element provided on the interface. When a sensitive element is defined in the enabled state, this element responds to the stresses produced by the User Gestures. When a sensitive element is defined in the disabled state, this element ignores the stresses produced by the User Gestures;

3) Set containing the display status of each sensitive element provided on the interface. When a sensitive element is defined in a visible state, that element appears in the interface. When a sensitive element is defined in invisible state, this element is not included among the elements displayed in the interface; 4) Set containing the position, shape and size data for each sensitive element provided on the interface;

5) Set of Symbols, operating conditions, interaction commands to be combined with the Buttons.

The input method provides that the User can view a set of Symbols from which to select; this set is not necessarily fully displayed. The aforementioned set of symbols is equipped with numerical indexes which identify the segment (or segments) of the set to be used in the graphic representation.

For this purpose, the following should be considered:

1) A set of Symbols. The elements of this set are identifiable on a positional basis with zero-based numbering.

2) A set consisting of pairs of indices. Each pair of indices identifies a particular segment in the set of Symbols. A segment must be considered as a set made up of Symbols, chosen contiguously from the set of Symbols; special cases are possible of segments consisting of empty sets (ie sets without Symbols), considered to have no effect for the purposes of this document. For each pair of indices, the first value identifies the starting position to be considered in the set of Symbols, while the second identifies the final position to be considered in the set of Symbols. A negative value index does not identify any position; pairs of indices consisting of negative values are allowed (such a pair of indices does not identify any segments). 3) Any pairs of indexes that have inconsistent values will be ignored for purposes in this document.

The User can interact with a Button through a contact on the corresponding area. Recognition of the occurrence of a contact with the Button occurs when the User touches a sufficient part of the area in question.

When a single Symbol is associated with a Button, the short touch involves selecting the Symbol.

When two Symbols are associated with a Button (one of which is designated as primary and the other as secondary), a short touch selects the main symbol, while a long press selects the secondary symbol.

The selection of a Symbol involves the remission of the code corresponding to that Symbol.

When an operating condition is associated with a Button, a numeric variable (hereinafter referred to as condition variable) is associated with this Button which describes the status of the operating condition, initialized to the value one, increased at each selection of the Button, and managed cyclically along a set of values equal to the number of possible states (consequently, if once the condition variable is increased its value exceeds the number of possible states, the value of the condition variable is set to one).

When an interaction command is associated with a Button, selecting the Button determines the execution of the aforementioned interaction command.

Figure 5 shows the schematic representation of the invention.

The geometric arrangement of the elements sensitive to interactions characterizes the invention because it is designed to allow a User to interact with the Device even only by means of the thumb while the Device is supported with one or both hands. The parts presented in figure 5 are divided as follows:

a) 7 (seven) buttons in correspondence with the distinct part at number 9. The centers of these buttons are arranged along an approximately elliptical arc, in accordance with the arrangement shown in the figure. Each of these buttons allows the selection of a Symbol;

b) 6 (six) buttons in correspondence with the distinct part at number 10. The centers of these buttons are arranged along an approximately elliptical arc, in accordance with the arrangement shown in the figure;

a) 5 (five) buttons in correspondence with the distinct part at number 15. These buttons are placed side by side according to a linear arrangement, in accordance with the arrangement shown in the figure;

b) 5 (five) buttons in correspondence with the distinct part at number 16. These buttons are placed side by side according to a linear arrangement, in accordance with the arrangement shown in the figure;

c) 1 (one) button corresponding to the distinct part at number 11.

This button allows you to activate the cancellation function; d) 1 (one) sensitive surface in correspondence with the distinct part at number 12. This button has the shape of a circular crown and is referred to below as Ring.

e) 1 (one) sensitive surface in correspondence with the distinct part at number 13. It consists of a circular sensitive surface, hereinafter referred to as Lever, of reduced dimensions compared to the Ring and contained in it.

f) 1 (one) button corresponding to the distinct part at number 14.

A short press of this button alternately activates or deactivates the upper case operating condition. A prolonged pressure of this button activates or deactivates, alternatively, the function of caps lock (so-called Caps Lock in English);

g) 1 (one) button corresponding to the distinct part at number 17. A short pressure of this button causes the emission of the space character (so-called Space in English); h) 1 (one) button in correspondence with the distinct part at number 18, intended to accommodate one or more Symbols of frequent use;

i) 1 (one) button corresponding to the distinct part at number 19.

Pressing this button for a short time determines the choice of the operating mode of the interface, progressively and cyclically addressing the possible modes provided in the table of operating modes. If enabled by suitable setting of the internal configuration parameter, a long press of this button causes the display of the configuration parameters.

j) 1 (one) button in correspondence with the distinct part at number 20 intended to accommodate one or more Symbols of frequent use.

Each Button has a shape and size defined as configuration parameters. In the absence of the respective configuration parameters, the default shape of the buttons of the parts identified at numbers 9, 10, 19 in figure 5 is a circle whose diameter is assumed to be equivalent to 11 millimeters.

When a Button is associated with one or more Symbols, its graphic appearance recalls the associated Symbol or Symbols.

In the event of contact with a Button to which no Symbol or condition or command has been associated, no code will be issued.

The following events are monitored on the surface of the Ring:

1) Contact with surface areas, in which the minimum useful granularity allows to distinguish areas corresponding to the upper, lower, left and right zones of the circular crown, managed in countable sections. Figure 5 indicates, near the distinct part at number 12, triangular-shaped elements, placed to highlight the aforementioned upper, lower, left and right areas; for the purposes of the contact event, the area is considered part of the Ring. In this case, following contact with any area of the Ring, special codes will be issued, in accordance with the configuration parameters. These configuration parameters are indicated for each portion of the area, as they are managed in discretized form. If these parameters are not specified, the default behavior will be assumed, i.e. the codes corresponding to the traditional keys known as `` Right arrow '', `` Up arrow '', `` Left arrow '', or `` Down arrow '' will be issued when the ™ User briefly touches an area near the right, upper, left, lower edge respectively. The prolonged touch on the same areas determines the emission of further codes, according to the configuration parameters. 2) Rotating movements performed by the User along the aforementioned circular crown or portions of it. Unlike a contact, a rotary movement is characterized by the displacement of the contact area for a distance greater than a predetermined threshold within a predetermined time interval. When the User performs a clockwise or counterclockwise movement, interaction commands are activated, in accordance with the configuration parameters. If these parameters are not specified, the default behavior will be assumed, i.e. in the face of a rotary movement, a scrolling command will be issued along the set of symbols affecting the parts identified at number 9, 10, 15, 16, 18, 20 of figure 5. The sliding is in the direction of advancement for the case of clockwise movements, and in the opposite direction for the case of anticlockwise movements.

The User can perform Gestures to use the Lever both as a button and as a repositionable element in the area inside the Ring; for this purpose the following events are identified on the surface of the Lever:

1) The User touches an area of the Lever without making significant movements, described later in the text. In this case the Lever reacts to the contact like a button. Pressing this button causes the emission of the code corresponding to the carriage return character (so-called Return in English);

2) The User touches an area of the Lever and performs relevant movements, defined later in the text. In this case, the Lever reacts to contact as an element that can be repositioned in the internal area of the Ring, ie in this area the User can drag the graphic element that represents the Lever. Once the dragging operation has been detected, the graphic element representing the Lever can be replaced by a smaller graphic element, in order to optimize the degrees of freedom of movement. In the management of the above events, the movements are identified as relevant when the distance traveled from the initial position where the contact occurred exceeds a fixed threshold. This distance is evaluated between the representative point of the initial contact area and the representative point of the current contact area. The distance between two points on the screen is evaluated on the basis of the canonical metric between two points on a Cartesian plane, i.e. the distance is expressed as the square root applied to the sum of the differences, each raised to the power of two, respectively between the coordinates horizontals and verticals of these points.

When the Lever is used as a repositionable element, during the dragging phase:

1) the graphic element representing the Lever is replaced by a graphic element of adequate size to allow optimization of the degrees of freedom of movement, where the dimensions mentioned are specified as a parameter (it should be noted that the value is irrelevant for the description of the operation);

2) the horizontal and vertical coordinates of the central point of the lever are modified according to the movements of the user. The deviation of the central point of the Lever is determined on the basis of a table containing pairs of values, in which the first value refers to the distance between the current position of the contact point and the rest position of the center of the Lever, the second value It refers to the deviation to be applied to the central point of the Lever. An intermediate value can be determined by interpolating the assigned values, with an approximation to the lower integer.

The positions allowed for the central point of the Lever are exclusively the positions for which the graphic representation of the Lever does not go beyond the boundaries of the ring.

When the lever is used as a repositionable element, at the end of the dragging phase it automatically returns to the central position which constitutes the rest position.

The use of the Lever determines the emission of codes based on configuration parameters. If these parameters are not specified, the default behavior described below will be assumed :.

1) If the current position of the Lever falls within the upper area of the Ring, the code corresponding to the Top Page (so-called Page Up in English) is issued;

2) If the current position of the Lever falls in the right-hand area of the Ring, the code corresponding to the forward tabulation character is emitted;

3) If the current position of the Lever falls within the lower area of the Ring, the code corresponding to the Lower Page is emitted (so-called Page Down in English);

4) If the current position of the Lever falls in the left area of the Ring, the code corresponding to the backward tabulation character is emitted.

The part identified at number 11 in figure 5 consists of a button having an approximately semicircular shape, which is assigned the function of canceling the last character entered.

A short-term contact on this button, in the absence of conditions that alter its function, causes the cancellation of a character with backward movement (so-called backspace in English). An extended duration contact on this button, in the absence of conditions that alter its function, causes the deletion of a character with forward movement (so-called delete in English).

The operating conditions of the aforementioned button may be altered if its use is preceded, in the absence of further intermediate interactions by the User, by the selection by the User of the upper case mode (see the description relating to the distinct part from number 17 in the graphics), following which the function assumed by the button would correspond to the deletion of a character with forward movement (so-called delete in English).

The part identified at number 17 in the graphical drawings consists of a button having the shape of a circular segment with a rectangular base, which is assigned the capital function. If the user chooses an alphabetic character when the uppercase function is activated, this character will be issued in the corresponding uppercase version if available, otherwise (if the uppercase version is not available) the character will be issued in the available version. The user can select or deselect the uppercase function by briefly touching the corresponding button. Once enabled, the caps function is automatically disabled when the user selects any symbol. The user can select any period for the upper case function, ie until the next deactivation, by means of a prolonged contact on the corresponding button; in this case a further contact (short or prolonged) on the same button will deactivate the caps function.

The part identified at number 19 in fig. 5 consists of a Button whose size is specified as a parameter. If this parameter is not specified, the Button consists of a circle with a diameter of 11 millimeters. Following a short touch of this Button, the list of symbols displayed in the parts identified at numbers 9, 10, 15, 16, 18 and 20 in figure 5 is modified.

If made possible by the characteristics of the device, the interface also reacts to scrolling gestures performed along each of the following functional complexes:

a) Assembly consisting of part 9 and part 10 indicated in fig. 5; b) Assembly consisting of part 15 and part 16 indicated in fig. 5; c) Assembly consisting of part 18 and part 20 indicated in fig. 5. When the User performs a Scrolling Gesture on one of these complexes, or when the User interacts by moving the thumb with a movement of crossing the parts that make up one of the indicated complexes, the Symbols displayed in the Buttons of this complex they are replaced by other Symbols, acquired in specific groups of predetermined Symbols. Symbol groups are subdivisions of the set of symbols. Each group of symbols is associated with one of the aforementioned complexes. Each group specifies both the main symbol and any secondary symbol to be associated with each button. The composition and consistency of the groups is specified through the configuration parameters, that is, it depends on the needs of specialization and localization.

The display alternation of the Symbols in the Buttons due to the scrolling Gestures is of a circular type, that is, once the display of the Symbols belonging to a group is completed, a further Scrolling Gesture in the same direction as the list of Symbols in the group is exhausted, determines the display of the first list of Symbols or the last list of Symbols in the group, as appropriate. Depending on the direction of the scrolling gesture on a complex, the list of symbols to be associated with the buttons of the complex is crossed in an ascending or descending direction.

The content and behavior of the Buttons and other sensitive elements can change, through the configuration parameters, according to specializations and localizations for specific countries and cultures. For each Button or other sensitive element, the following can be specified: appearance, one or more activation conditions (short touch, long touch, Scroll gesture on a complex in ascending direction, Scroll gesture on a complex in descending direction, circular movement clockwise along the crown identified by part number 12 in fig. 5, circular movement counterclockwise along the crown identified by part number 12 in fig. 5, relevant movement applied to part number 13 in fig. 5) and the respective actions to be performed (issue of one or more numeric codes, and / or modification of an operating condition such as upper case status, and / or execution of a command such as displaying a list of Symbols in a complex, and / or execution of actions equivalent to a pointer - so-called mouse in English - such as vertical scrolling and clicking). In case of bilateral display, the parameters are independent. Figure 6 shows the implementation of the interface for input requirements with alphabetic characters. In this embodiment, the buttons of the assembly corresponding to the distinct parts at numbers 9 and 10 in fig. 5, contain alphabetic symbols from letter A to letter M according to the arrangement illustrated in fig. 6. The distinct part at number 21 of fig. 6 highlights one of the Buttons configured to allow the choice between two Symbols.

Figure 7 shows the implementation of the interface for the needs of entering alphabetic and numeric characters. In fig. 7 the distinct part at number 22 indicates the assembly corresponding to the distinct parts at numbers 15 and 16 in fig. 5, containing numbers from 0 (zero) to 9 (nine) according to the illustrated arrangement. In fig. 7 the distinct part at number 23 indicates the graphical representation Lever when used as a repositionable element, that is once the User applies significant movements on the corresponding area, distinct from part number 13 of fig. 5, when it is in the rest position. In fig. 7 the distinct part at number 24 indicates the complex corresponding to the parts identified at numbers 18 and 20 in fig. 5, containing the asterisk and hash symbols. In fig. 7 the distinct part at number 25 indicates the assembly corresponding to the parts identified at numbers 9 and 10 in fig. 5, containing contains alphabetic symbols from letter N to letter Z according to the illustrated arrangement. The variations found between fig. 6 and fig. 7 for the single complexes described are obtained by applying scrolling gestures along each of the complexes of interest, and / or using the Buttons configured for this purpose.

Claims (1)

CLAIMS 1) The arrangement of the buttons with respect to each other in a keyboard (so-called keyboard layout in English) characterized by buttons placed to form two overlapping arcs in which the upper arc (9) includes seven circular buttons while the lower arch (10) includes six circular buttons, from a row of five adjacent square buttons (16) placed at the base, from a row of five adjacent square buttons (15) placed immediately above the previous row, from a button shaped semicircular (11) whose base is laid along the right perimeter and placed immediately below the top circular button of the lower arch, by a button in the shape of a circular segment (14) with an edge resting on the perimeter and the other edge lying at the edge of the upper row of square buttons (15), by a semicircular-shaped button (17) whose base lies along the perimeter of the upper row of buttons squares (15) on the vertical of the third and fourth buttons - counted starting from the button in contact with the right perimeter - of said upper row (15), by a button (18) placed at the left end of the upper row of buttons square (15), by a button (20) located at the left end of the lower row of square buttons (16), by a circular button (19) immediately to the left of the aforementioned button (20) at the end of the lower row of square buttons, and a multifunction button with semi-central location (12; 13). The lower button in the lower arc is located next to the leftmost button in the upper row of square buttons. Each button can be marked with letters, numbers, punctuation symbols. Purely by way of example, a realization of the layout of the buttons in the keyboard layout for the Italian language is shown, in which (Fig. 6) the circular buttons located along the upper arch (9) are combined with the characters â € œAâ € , â € œBâ €, â € œCâ €, â € œDâ €, â € œEâ €, â € œFâ €, â € œGâ € (starting from the circular button placed further down between them), to the circular buttons placed along the lower arch (10) combines the characters â € œHâ €, â € œIâ €, â € œJâ €, â € œKâ €, â € œLâ €, â € œMâ € (starting from the circular button placed further between them), the square buttons of the upper row are combined with the characters â € œNâ €, â € œOâ €, â € œPâ €, â € œQâ €, â € œRâ € (starting from the square button located furthest to the left in the row), the characters â € œSâ €, â € œTâ €, â € œUâ € / â € œXâ €, â € œVâ € / â € œYâ €, â € œZâ € / â € œWâ € (starting with the leftmost square button in the row), to the button and multifunction (12; 13) with semi-central position the wording â € œEnterâ € is combined with the semicircular button (11) located near the lower arch is combined with the words â € œBackspaceâ €, with the button in the shape of a circular wedge (14 ) The wording â € œShiftâ € is combined with the semicircular button (17) located above the upper row of square buttons (15) The wording â € œSpaceâ € is combined with the button (18) adjacent to the upper row of square buttons (15) the character â € œ @ â € is associated to the button (20) adjacent to the lower row of square buttons the character â € œ # â € is associated to the circular button (20) next to the last button mentioned is combined with the wording â € œModeâ €.