SC-691

The SC-691 is a standard slave synthesizer from Sensory, Inc. that accepts compressed speech data from other microprocessors or microcontrollers and converts it to speech.

This allows the SC-691 to be used with a master microprocessor/microcontroller in various speech-related products such as security systems, learning aids, games, and toys. High quality, low bit-rate coders, easy interface with the master microcontroller, digital gain control, low power sleep mode, and low voltage operation makes this device ideal for products requiring long duration speech, less development cycle times, and peripheral device control through the slave device.

  
This device supports several speech synthesis algorithms that permit tradeoffs to meet the price performance requirements of various markets.

The SC-691 implements a unique feature of playing a single channel FM music along with CX or MX speech data concurrently. This feature allows the user to speak a certain phrase in MX or CX with single channel music in the background.

The SC-691 is optimized to support a 4-bit wide data transfer protocol. The device has two status bits and three control bits that control the communication protocol between the master and the slave.

The SC-691 also has 1 bit (command/data) which differentiates between a command and speech data feeding into the slave. In 4-bit mode, various commands are sent to the slave during speech to perform various tasks.

The SC-691 also supports the 8-bit wide data transfer but the support for commands is disabled during speaking-a-phrase. When speaking-a-phrase in 8-bit mode is complete, the SC-691 switches back to the 4-bit mode to receive the next command. Switching between 4 bit mode and 8 bit mode is permitted between speech data files.