Arrangement for transferring data to a centrex

Abstract

An arrangement for tranmitting data messages between a remotely located attendant console and a CENTREX equipped central office exchange. The arrangement includes an operating unit residing in an interface circuit connected between the attendant console and the central office exchange. The operating unit of the present invention includes receiving circuitry connected to the attendant console and to a controller. The receiving circuitry is arranged to receive a data message from the attendant console and set a receive signal. A state machine called by the controller transfers the first byte of the data message to a temporary memory and resets the receive signal. The state machine accepts all additional characters from the receiving circuitry storing received characters in the memory until a character sequence is received indicating the end of the data message. When a complete data message is received an analysis is called by the controller which analyzes the received data message. Sequential memory receives and stores the data message from the memory responsive to the analysis concluding that the data message is for the peripheral processor. The controller then sends a control signal to the CENTREX via the sense field indicating a data message has been stored in the sequential memory and is available for transfer.