Abstract: A radio system (100) includes a plurality of addressable processors (150, 180, and 200). A communication link (230) interconnects the addressable processors (150, 180, and 200). The communication between the addressable processors is conducted via a first and a second communication protocols. The first communication protocol includes a plurality of fixed length information packets for passing parametric data to or from the addressable processors at a fixed baud rate including a packet for changing the communication protocol. The second communication protocol includes a plurality of variable length information packets for passing parametric data to or from the addressable processors at selectable speeds. Whereby the operating state of the addressable processors may be determined or altered by, respectively, communicating parametric data from or to the addressable processor at variable baud rates.

Abstract: A method and device for enabling writes to a memory unit. The memory write device, such as a microprocessor (11), must provide a predetermined sequence of addresses to an address decoding unit (13), which then passes along the decoded addresses to a memory write enable unit (14). If the correct sequence, and only the correct sequence, is so provided, the memory write enable unit (14) will provide an enable signal (16) to the memory (12), thereby allowing the microprocessor (11) to write to the memory (12). A timer (26) can be utilized to limit the enable window.

Abstract: A multiple interrupt tri-level microprocessor operating system (40) having particularly applicability in a two-way radio, includes an operating system that provides a background executive (47) to allow processing of time insensitive tasks, a foreground routine (24) to allow processing of real-time sensitive tasks, and a midground executive (41) to allow processing of time sensitive tasks. The midground executive (41) provides for periodic execution of preselected tasks, which tasks can all be completed within a predetermined period of time.

Abstract: A programming station for use in programming and servicing two-way radios. The station allows a user to read stored radio control and radio feature parameters as stored in either a radio or an archive file. The station allows the user to modify at least some of the radio feature parameters, and to access a remote central unit that allows modification of the remaining radio feature parameters. The changed parameters can then be merged as necessary and stored in the radio and/or an archive file.

Abstract: A telephone interconnect system for a two-way radio communications system is disclosed. A telephone patch interconnect unit accepts dialed digits from a telephone line, encodes them into a data packet, and couples the data packet to a fixed transceiver for transmission to remote units. A remote unit with a digit sequence identification matching the received and decoded dialed digit activates an alert. A remote unit may generate and store digits corresponding to a desired telephone number. The digits are subsequently encoded into a data packet and transmitted to the telephone patch interconnect unit. The interconnect unit accepts, acknowledges and decodes the data packet and couples the resulting digits to the telephone line.