摘要:
A communication system including a master station, a plurality of slave stations each for communicating with the master station, a two-way transmission line connecting the master station and the plurality of slave stations. Each of the slave stations sends a request for further communication with the master station, to the master station when its own slave station is allowed to communicate with the master station and its own slave station has the above request. The master station detects the request for further communication with the master station in a signal sent from a slave station, and memorizes the slave station from which the request for further communication with the master station is detected, until an allowance signal is sent to the slave station from the master station corresponding to the memorizing of the slave station. The master station has a cyclic address pointer which points to an address of a next one of the slave stations in a cyclic order when no slave station is memorized in the master station. The master station outputs the allowance signal to communicate with the master station to a slave station which is memorized in the master station or to a slave station the address of which is pointed to by the cyclic address pointer when no request is memorized in the master station.
摘要:
A communication system containing a master station and a plurality of slave stations. The master station receives a request from one of the plurality of slave stations and memorizes one or more requests from one or more slave stations. The master station also sends a request sending allowance signal which addresses one of the plurality of slave stations to give an allowance to send a request for sending data, and sends a data sending allowance signal which addresses one of the plurality of slave stations to give an allowance to send data, according to a request which is memorized. Each of the slave stations detects a request sending allowance signal which addresses its own slave station, and a data sending allowance signal which addresses its own slave station. Each of the slave stations also sends a request for sending data to the master station when its own slave station detects a request sending allowance signal which addresses its own slave station. In addition, each slave station sends data to the master station when its own slave station detects a data sending allowance signal which addresses its own slave station.
摘要:
A coded transmission system wherein each bit of transmitted data having a logical value is coded depending on a coded result of a preceding bit. The coded transmission system contains a sender-side apparatus, a transmission line, and a receiver-side apparatus. In the sender-side apparatus, a resetting bit and a message are generated; a code of a bit last transmitted which is necessary to code a bit which is to be transmitted next is memorized in a first preceding code memorizing circuit; and the content of the first preceding code memorizing circuit is reset to an initial code responding to the resetting bit. A coding circuit receives the resetting bit and the message, codes each bit of the message in accordance with a predetermined coding rule and the content of the first preceding code memorizing circuit, and codes the resetting bit to a predetermined resetting code which is different from the codes used in the coding of the message. In the receiver-side apparatus, a code of a bit last received which is necessary to decode a code of a bit which is received next is memorized in a second preceding code memorizing circuit. A resetting circuit resets a content of a second preceding code memorizing circuit to a predetermined initial code when receiving the resetting code. A decoding circuit decodes the received codes corresponding to the message in accordance with the predetermined coding rule and the content of the second preceding code memorizing circuit.
摘要:
In a sequential polling type communication network system including a master station, a first channel, a second channel, and at least two slave stations, the master station includes request registration units for registering data transmission requests from slave stations during a data transmission by another slave station, and an interrupt polling unit for polling the slave station which has issued the data transmission request after completion of the data transmission or completion of a polling of a slave station, and the slave station includes a unit for responding to a polling during the data transmission, and transitting a data transmission request when data to be transmitted exists, and for responding to the interrupt polling from the master station, and transmitting the data to the master station until the data transmission is completed.
摘要:
Disclosed is a frame synchronizing apparatus in a receiving equipment for receiving digital signals for PCM communication. The digital signals consists serial signals at a rate of f.sub.0 (bps). The serial signals include a frame synchronizing signal consituting n bits or a part of the frame synchronizing signal, collectively arranged in one frame. To attain a high-speed operation and a shorter synchronization establishing time, the apparatus comprises a latching circuit for converting the serial signals into parallel signals and for latching the parallel signals, and a circuit for detecting a plural number of times of synchronization during the n bit interval in one frame.
摘要:
An optical bus type communication system comprises a bus type transmission line consisting of an optical fiber, a light source provided at the one end of the bus type transmission line for sending an optical signal having a constant level to the bus type transmission line, a plurality of optical switches mounted on the bus type transmission line, and a plurality of terminal interfaces. Each terminal interface sends data by switching the corresponding optical switch so that the optical signals on the transmission line are modulated with the data.
摘要:
A circuit which operates at the fixed timing and discriminates the control signal is provided and the timing pulse for demultiplexing is controlled in accordance with the discriminated control signal in the receiving part of the synchronized multiplexing system in which the basic signals are generated by inserting the control signal required for multiplexing on the frame structure of basic signal rate and the high level multiplexing signal is formed by multiplexing such basic signals, thereby stable correspondence between the channel at the time of multiplexing in the sending side and the channel after the demultiplexing in the receiving side can be ensured.
摘要:
An inter-network connecting system comprising a main network having an exchange function and a subnetwork having no exchange function, to improve the expandability, economy, and efficiency of the subnetwork. When an extension line communication which is a communication in the subnetwork is to be carried out, a call setting processing processor in the main network gives a calling terminal a first special signal so as to operate lookback means in a connection control unit in the subnetwork to set a physical communication paths for an extension line between terminals in the subnetwork; and when an outer line communication which is a communication between the main network and a terminal in the subnetwork is to be carried out, the call setting processing processor gives a calling terminal a second signal so as to stop the operation of the loopback means in the connection control unit to set a physical communication path for an outer line between the exchange and the terminal in the subnetwork.
摘要:
In a multiple access system for a communication network in which a main station (M) is coupled to a plurality of sub stations (S1-Sn) via lines, each sub station (S1-Sn) comprises a data buffer (1) for storing data (DATA-TE) which is to be transmitted, and a request information forming part (2) for sending to the main station (M) transmission request information (REQ) which includes reservation information obtained based on a data quantity (IN) stored within the data buffer, and the main station (M) comprises a control part (5) for forming a time table (3) of a data transmission reservation time and a corresponding sub station number based on the reservation information included in the transmission request information from each sub station and for giving authority to transmit data to each sub station by transmitting a data transmission enable signal (TENO) to each sub station depending on the data transmission reservation time and the sub station number of the time table.
摘要:
A cross-point type switch includes a plurality of basic elements arranged in rows and columns so as to form a matrix arrangement of the basic elements. Each of the basic elements includes a plurality of input ports, output ports, expanded input ports and expanded output ports. A write/read part is connected to a common memory and has the function of writing data into the common memory and reading out the data from the common memory. A selector part selectively outputs either the data read out from the common memory or data from the expanded input ports to the output ports. The expanded output ports are directly connected to the input ports.