Abstract: A voice store and forward telecommunications system that provides for the receipt, storage and retrieval of voice messages is described. The system design allows for messages to be received and stored to a mass storage device, messages and prompts to be retrieved from the mass storage device and issued, and DTMF commands to be received simultaneously with the issuance of messages and prompts without conflict. Multiple user telecommunication channels are supported by the system, all in real time. Channel interface processors communicate with a system control processor through paired message segment buffers alternately swapped into the address space of the system control processor. A directory and allocation table corresponding to the mass storage device is maintained by the system control processor in a RAM buffer to permit real time storage and retrieval of messages.

Abstract: An electronic circuit is disclosed which is capable of producing synthesized sounds under the control of a microprocessor or other type computer. A plurality of switch inputs are provided whereby the sound to be produced can be selected. The processor, under program control, then generates such sounds utilizing one or more basic waveforms stored in a memory. These basic waveforms are modified in specified ways and then outputted through an I/O device to a digital to analog converter for application to an audio system. Eight input control lines to the microprocessor also feed an 8-input NAND gate, such that a momentary change of the normally-high control inputs will cause the NAND gate to activate an interrupt request.