System and method for communicating with digital and analog devices via a single digital interface

• US 5,483,530 A
• Filed: 12/16/1993
• Issued: 01/09/1996
• Est. Priority Date: 12/16/1993
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Dillon, Charles B., Davis, Gordon T., Marks, Laurence V.
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): VU, HUY DUY
• Application Number:
  US08/166,996
• Time in Patent Office: 754 Days
• Field of Search: 370/91, 370/85.13, 370/92, 370/93, 370/94.1, 370/94.2, 370/110.1, 370/77, 370/79, 370/110.2, 370/110.3, 370/110.4, 370/53, 370/58.1, 370/58.2, 370/68.1, 375/5, 375/7, 375/8, 379/90, 379/93, 379/94, 379/102, 379/105, 455/4.1, 455/4.2, 455/6.3, 455/68, 455/69, 455/70, 455/92, 455/353
• US Class Current: 370/465
• CPC Class Codes: H04L 25/4927 using levels matched to the quantisation levels of the channel
• CPC Class Codes: H04Q 11/0428 Integrated services digital network, i.e. systems for transmission of different types of digitised signals, e.g. speech, data, telecentral, television signals
• CPC Class Codes: H04Q 11/0471 Terminal access circuits
• CPC Class Codes: H04Q 2213/034 Codec; PCM compression
• CPC Class Codes: H04Q 2213/09 Subscriber related equipment; Analog terminal
• CPC Class Codes: H04Q 2213/096 Digital subscriber terminal
• CPC Class Codes: H04Q 2213/13031 Pulse code modulation, PCM
• CPC Class Codes: H04Q 2213/13034 A/D conversion, code compression/expansion
• CPC Class Codes: H04Q 2213/1309 Apparatus individually associated with a subscriber line, line circuits
• CPC Class Codes: H04Q 2213/13103 Memory
• CPC Class Codes: H04Q 2213/13107 Control equipment for a part of the connection, distributed control, co-processing
• CPC Class Codes: H04Q 2213/13176 Common channel signaling, CCS7
• CPC Class Codes: H04Q 2213/13199 Modem, modulation
• CPC Class Codes: H04Q 2213/13202 Network termination [NT]
• CPC Class Codes: H04Q 2213/13209 ISDN
• CPC Class Codes: H04Q 2213/13292 Time division multiplexing, TDM
• CPC Class Codes: H04Q 2213/13299 Bus
• CPC Class Codes: H04Q 2213/1332 Logic circuits
• CPC Class Codes: H04Q 2213/13396 Signaling in general, in-band signalling
• CPC Class Codes: H04Q 2213/179 Facsimile; Fax, e.g. still picture

Abstract

The invention is an ISDN terminal equipment which will maintain connectivity with existing analog modems by setting up a voice-grade connection to existing analog modems and using the power of a digital signal processor DSP to generate the digital equivalent of the analog modem signals for transmission on an ISDN "B" channel.

Claims

1. A system for providing information telecommunication services between a computing device and a selected one of plurality of diversely equipped analog and digital devices remotely linked to said computing device through parts of a public switched network, said computing device being required to be able to process information contained in signals transferred to said computing device via said network, said system comprising:

a single digital channel for carrying signals between said computing device and said network;

said digital channel carrying digitized log PCM signals representing diverse types of information when said remote device is an analog device in nature, said digital channel carrying various other digitally formatted signals when said remote device is a digital device in nature said log PCM signals being incompatible in form with information signal processing requirements of said computing device, and therefore the information content of said signals is not directly processable by said computing device while said signals are in said log PCM forms, wherein said digital channel is connected to said network via a data link; and

digital signal processing means for coupling said computing device with said digital channel for exchanging signals in diverse signal forms compatible with requirements of said remote devices, and for exchanging signals with said computing device in forms directly compatible with information processing requirements of said computing device but incompatible with signalling requirements of said remote devices, and for converting said signals in transit between said computing device and said digital channel into forms respectively compatible with said signalling requirements of said devices and said computing device,

wherein said computing device comprises, a system manager configured to provide a high level interface to said digital signal processor means, a port manager configured to support all call control functions performed by said digital signal processor means, and a plurality of drivers, coupled to said port manager and said system manager, for activating tasks in said digital signal processing means to dynamically support telecommunication with said remote devices.

2. The system according to claim 1, wherein said data link is an ISDN "B" channel and one of said plurality of drivers is an ISDN driver.

3. An computing device adapter card for providing information telecommunication services between the computing device and a selected one of plurality of diversely equipped analog and digital devices remotely linked to the adopter card through a public switched network, the adaptor card being required to be able to process information contained in signals transferred to the adaptor card via the public switched network, the adaptor card comprising:

a single digital channel for carrying signals between the computing device and the network, said digital channel carrying digitized log PCM signals representing diverse types of information when the remote device is an analog device, and said digital channel carrying various other digitally formatted signals when the remote device is a digital device, said log PCM signals being incompatible in format with information signal processing requirements of the computing device, wherein said digital channel is connected to the via a data link; and

digital signal processing means coupled to the computing device via a bus interface and also coupled to said digital channel for exchanging signals in diverse signal formats compatible with requirements the remote devices, and for exchanging signals with the computing device in formats directly compatible with information processing requirements of the computing device but incompatible with signalling requirements of the remote devices, and for converting said signals in transit between the computing device and said digital channel into formats respectively compatible with said signalling requirements of the remote devices and the computing device,

wherein said digital signal processing means comprises, a system manager configured to provide a high level interface to the computing device, a port manager configured to support all call control functions performed by said digital signal processor means, and a plurality of drivers, coupled to said port manager and said system manager, for activating tasks in said digital signal processing means to dynamically support telecommunication with the remote devices.

4. The adapter card of claim 3, wherein said data link is an ISDN "B" channel and one of said plurality of drivers is an ISDN driver.