Multiple access data communications controller for a time-division multiplex bus

• US 4,603,418 A
• Filed: 07/07/1983
• Issued: 07/29/1986
• Est. Priority Date: 07/07/1983
• Status: Expired due to Term

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Townsend, Greg M.
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Scutch, III, Frank M.
• Application Number:
  US06/511,804
• Time in Patent Office: 1,118 Days
• Field of Search: 370/95, 370/96, 370/85, 370/104
• US Class Current: 370/449
• CPC Class Codes: H04Q 11/04 for time-division multiplexing H04Q11/0001 takes precedence
• CPC Class Codes: H04W 84/08 Trunked mobile radio systems

Abstract

Method and apparatus are provided for control of a dedicated data slot in a time-division multiplex system for both voice and data communications enabling equal access to the data slot, efficient data throughput and reliability.

Claims

1. A multiple access data communications controller for unifying the operation of a plurality of synchronous communication nodes and a time-division multiplex bus comprising:

(a) means for sequentially polling each of a plurality of synchronous nodes;

(b) means for receiving a signal from a synchronous node;

(c) means for simultaneously granting control of a predetermined data slot on the time-division multiplex bus to said requesting node for a predetermined time and inhibiting said sequential polling means;

(d) means for resuming sequential polling at the node following said requesting node in the sequence, whereby each of said plurality of nodes is provided equal access to a predetemined data slot; and

(e) timing means for synchronizing the operation of said synchronous nodes, said time-division multiplex bus and said multiple access data communication controller.

2. The apparatus as claimed in claim 1 further comprising means for relating each of said nodes to a predetermined time slot on the time-division multiplex bus.

3. A multiple access data communications controller for use in a communications system providing for bi-directional audio and data transfer between a plurality of nodes and including a time-division multiplex bus connecting the nodes with a unique one of the recurrent time slots defined by the time-division multiplex bus corresponding to each of the plurality of nodes and a dedicated recurrent data time slot, said controller providing equal access to the dedicated data slot to each of the nodes comprising:

timing means for enabling synchronous operation with the time division multiplex bus;

means for sequentially polling each of the plurality of nodes;

means for receiving a requesting signal from a requesting node;

means for simultaneously granting control of the data time slot to said requesting node and inhibiting said sequential polling means for a predetermined time;

means for enabling designated one of the plurality of nodes to receive data; and

means for resuming sequential polling at the node following said requesting node in the sequence.

4. The apparatus as claimed in claim 3 wherein said timing means for enabling synchronous operation with the time-division multiplex bus include a bit rate clock means, counter means coupled to said bit rate clock means for generating a start-of-frame signal and data clock means.

5. Method of assigning a dedicated data slot on a time-division multiplex bus to one of a plurality of nodes such that each of the plurality of nodes has equal access to the dedicated data slot, the method comprising the steps of:

(a) sequentially polling the plurality of nodes;

(b) receiving a requesting signal;

(c) inhibiting the polling and simultaneously granting control of the dedicated data slot to said requesting node for a predetermined time; and

(d) resuming sequential polling following said requesting node.