4 General
22.0303GPPMan-Machine Interface (MMI) of the User Equipment (UE)TS
4.1 Basic philosophy
The basic idea behind the present document is that it should give a minimum level of requirements, with emphasis on items which are seen as important from a usage point of view. This means, that the requirements are mainly dealing with standardized control procedures of access to services i.e. call establishment, invocation of supplementary services and so on.
The requirements on the physical layout of input and output features are kept to a minimum to allow for differentiated types of Ues and to ease the introduction of future developments in the area of MMI. The standardized control procedures describe the sequence of real actions to be taken by the users. However, since the requirements on the physical input features are minimal the control procedures may differ between Ues depending on the solution of the manufacturers. The "bridge" between these requirements is however that the same logical actions have to be taken by the user. That is, the user has to provide the same information for the call control and signalling no matter what the method is. This is also valid if an automatic device is used for carrying out the same actions. The logical procedures are therefore defined and standardized in the present document.
Optionally, the user may set the ME to disable some or all of the MMI functions defined in the present document. This setting shall only apply when the same SIM/USIM is in use otherwise the ME shall enable the standard MMI.