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- 1076.3 Scope of AT commands
- 112 1137 Gap analysis
- 119There are, in principle, three types of gaps concerning AT commands
- 1257.2.2 Cursor control
105106The list in table 1, from [1], cannot be considered to be exhaustive but it provides some indication of the extensive range of possibilities for interconnecting external devices to ICT systems. An important category of external devices not listed in table 1 is “Software for Total Conversation” with classification code 21 36 90. As can be seen, in some cases the external device may be a mainstream device normally used for another purpose (e.g. a mobile phone used as a text phone).1076.3 Scope of AT commands108Originally developed for computer modems in 1977 by Hayes Microcomputer Products, AT commands have matured from being a modem control technology to be a comprehensive and pervasive middleware platform for communication devices. AT commands provide control of calls, the SIM card, phone information, phone settings, packet domain, network services, and mobile termination in the communication device [6]. Currently, sets of AT commands has been standardized, but only a few AT commands of these are mandatory. However, many communication devices do not have this standardized set fully implemented. In addition, a number of manufacturers of communication devices have extended the AT command set to cover additional functions in the phone such as file storage, camera, etc. The manufacturers have gathered these extensions to the AT command set as company specific documents, some of which are publicly available, some of which are not. It is likely, though difficult to verify, that not all communication devices from the same manufacturer will have the full set of standardized and proprietary AT commands implemented within it.1096.4 Limitations110Currently, there is only a very limited range of assistive solutions available for communication devices, as the adaptations used by people with disabilities are only compatible with a few models of communication devices. External device and adaptation developers state that this is due to selective implementations of the standard AT command set, since not all of the commands specified in 3GPP TS 27.007 are mandatory [6]. Therefore, the external devices need to be tuned to match each specific communication device model. The consequences are higher development costs of external devices and also that the external device users only have limited choices when acquiring a new communication device (see scenario in appendix II). Also, these users might be limited to doing very basic tasks such as making and receiving calls and use the SMS service.111Realistically, it is understood that new communication device technologies are developing rapidly. Therefore the standardized AT command set will need to be periodically updated and revised. All communication devices should by definition carry the standardized AT command set in a firmware library and use the subset of AT commands necessary to make the particular phones functions available to users. In this way, external device manufacturers (or indeed any company interested in making generic accessories for communication devices) will have the confidence to know that an adaptation will work with all devices that have the function being adapted.1121137 Gap analysis1147.1 Introduction115In order to identify the gap between what is available and what is the needed, an analysis has been performed in order to investigate whether additional standardized AT commands are needed.116The gaps were identified in two ways:
117The needs of users with disabilities, as well as the need for new standardized AT commands, were identified through stakeholder input such as questionnaires, interviews, emails and workshops.118The annex and appendixes provide further details on how the gap analysis has been performed. The input to the gap analysis of the functionalities of communication devices versus standardized AT commands is summarized in annex A. Appendix I A provides details on issues related to various communication devices. Appendix II illustrates various user scenarios.119There are, in principle, three types of gaps concerning AT commands:
120In practice, the functionalities listed below as a implementation gap, depend on communication device type. Some of the functionalities described below as standardization gaps, may for some communication device types, not have any proprietary AT commands and could therefore be considered as belonging to sub-clause 7.2.1217.2 Complete gaps122Comparing the functionality of a typical communication device with the available standardized or proprietary AT command sets, the gaps described in the following sub-clauses were found. More details on the gap analysis is provided in annex A.1237.2.1 Colour124Visually impaired people often find it easier to read if a specific text and background colour is used. Many dyslexic people find it easier to read when the text is on a background with a specific colour.1257.2.2 Cursor control126Mobility-impaired users may need alternative pointing devices (e.g. stylus, finger, head pointer) to control the on-screen cursor.Directory: tr-30 tr-30 -> Ansi/tia-921-b network Model for Evaluating Multimedia Transmission Performance Over the Internet Protocol tr-30 -> Document submitted to Download 468.34 Kb. Share with your friends:
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