D6385A All Digital Telephone Answering Device with True FULL Duplex SpeakerPhone includes Slave CODEC Operation for Digital Telephone Applications General Description The D6385A chip is a digital speech/signal processing subsystem that implements all functions of TRUESPEECH speech compression and voice prompts, telephone line signal processing, memory management, FLEXISPEECH and True FULL Duplex SpeakerPhone for an all digital answering machine. In addition, the D6385A has the ability to operate as a CODEC, in slave mode, for use in Digital Telephone applications such as DECT. The D6385A is fully controlled by the system Host through a simple interface protocol. The Host controller provides activation and control of all system functions such as speech recording and playback, DTMF and call progress tone detection, DTMF and tone generation, and voice prompting. Phone Line Telephone Line Interface Speaker Phone Interface CODEC CODEC A D6385A DSP Speech Processor Host Controller Voice Prompt ROM ARAM Memory Optional Figure 1. D6385A System Block Diagram Key Features n High-quality, variable low rate TRUESPEECH digital speech compression allowing 14-15 minutes of recording time per each 4 Mbit ARAM (Audio Grade DRAM) n TRUESPEECH, natural-sound voice prompting, for Day/Time stamp and voice instructions n Flexible storage of incoming messages (ICM), outgoing messages (OGM). Supports multiple OGMs and multiple mailboxes n DTMF generation and detection with near-end echo cancellation for superior performance n Storage of 32 telephone numbers for speed dialing n Easy Host software conversion from the D6305B n FLEXISPEECH variable speed, natural sound playback (50%-200%) n Selectable Master/Slave CODEC operation n Supports offset playback for jumps within a message n True FULL Duplex SpeakerPhone with both acoustical and near-end echo cancellation n Programmable thresholds for VOX, DTMF, and call progress n Digital Volume Control n Two programmable call progress tone filters n Simple 8-bit Host Hardware Interface A D6385A Device Configuration and System Components STANDARD COMPONENTS n D6385A-11 Digital Telephone Answering Device (TAD) processor (80-pin PQFP)1 each ADDITIONAL SYSTEM COMPONENTS These are supplied by the customer according to DSP Groups specifications n D0000-29 Analog I/O Interface (16-pin DIP)1 each, 2 for SpeakerPhone One of the following: n D0000-35B/C* - 4Mb ARAM message memory (SOJ), up to four devices per system, or n D0000-36B/C* - 16Mb ARAM message memory (SOJ), up to two devices per system OPTIONAL SYSTEM COMPONENTS n EPROM/ROM - Voice Prompt storage, each 32Kx8 device supports up to 35.4 seconds of Voice Prompts (up to 64K) * Note: D0000-35C or D0000-36C are required if FLEXISPEECH is desired G LA F C C C N 0 9 8 S N N 7 7 6 7 C D G V 5 7 C 4 7 1 0 D D D 1 D A 2 7 8 7 6 D D D D R 0 7 R D A 8 6 R D A 9 7 R D A A 1 7 9 D R R D A 1 1 R D 3 7 2 D R D N 3 1 T A A NI C 8 7 IT 7 6 D A A 6 6 5 6 6 ADDR15 1 64 ADDR5 ADDR14 2 63 ADDR4 ACK 3 62 ADDR3 HI/LO 4 61 ADDR2 HSTRD 5 60 ADDR1 HSTWR 6 59 ADDR0 HSTDB7 7 58 MDB15 HSTDB6 8 57 MDB14 HSTDB5 9 56 NC HSTDB4 10 55 NC HSTDB3 11 54 GND HSTDB2 12 53 VCC HSTDB1 13 52 MDB13 HSTDB0 14 51 MDB12 GND 15 50 MDB11 NC 16 49 MDB10 XOUT 17 48 MDB9 XIN 18 47 MDB8 VCC 19 46 MDB7 SCLK 20 45 MDB6 RESET 21 44 MDB5 PDN 22 43 MDB4 FSYNC 23 42 MDB3 DX1 24 41 MDB2 A Top View D6385A-11 5 6 2 2 D X 0 1 R D 7 9 8 2 0 2 2 S D R 0 4 3 3 3 5 3 3 6 3 1 D C 2 3 R C C G V C C R S A S A N C 8 3 W D M 0 3 4 0 1 D D C R D N N A 9 3 C S A S 7 3 0 A R 2 1 3 P R E Figure 2. D6385A-11 Pin Diagram B M B M A D6385A System Functions All of the speech processing tasks are done by the DSP Speech Subsystem. This allows the use of a very low cost microcontroller to be used for basic control of the system. The Host need only send high level commands to perform functions such as Record Message or Delete Message and the operation will be performed by the DSP subsystem which will report the status of the operation to the Host. All memory interface and management will be taken care of by the DSP requiring the Host to only handle high level system functions. A summary of the functions performed by the DSP Speech Subsystem and Host Controller are shown in Figure 3, below. DSP Speech Subsystem n n n n n n n n n n n Host Controller n Control the System n Read Buttons n Control Displays / Switches Speech Recording Speech Playback Memory / Message Management DTMF and Tone Genertion DTMF Detection Call Process Detection Time / Date Stamping Voice Prompts Phone Number Storage SpeakerPhone Functions Slave CODEC Operation Figure 3. System Functions Simple Hardware Interface The hardware interface between the D6385A and the Host Controller is a simple one requiring only an 8 bit parallel port and 4 handshake lines. The Host writes high level Commands to the D6385A and the D6385A will respond with Status information. Once a Command is issued the D6385A will use the ACK pin to indicate that the Status is available to be read. The hardware interface between the D6385A and Host is shown in Figure 4 below. 8051 Port 0 RD WR HI/LO INT D6385A-11 8 HSTD0-7 HSTR HSTW HI/LO ACK Figure 4. D6385A / Host Interface Benefits of the D6385A n High-Quality, variable low rate TRUESPEECH digital speech compression allowing 14-15 minutes of recording time in 4 Mbits of ARAM n The Host selectable thresholds for VOX, DTFM and Call Progress allows flexibility in design for various countries and different applications n TRUESPEECH natural sounding voice prompts and time/date stamping allow design of a high quality and professional sounding product n The True Full-Duplex SpeakerPhone capability allow a very professional sounding SpeakerPhone to be added to your product with a very minimal additional cost n Operation as a Slave CODEC Reduces the system cost by eliminating the need for an extra CODEC n Allows flexibility in design for features such as multiple mailboxes and multiple OGMs allowing design of a product that is truly a Personal Voice Mail System TRUESPEECH is a registered trademark, and FLEXISPEECH and True FULL Duplex SpeakerPhone are trademarks of DSP Group, Inc. Other company and product names mentioned in this document may be the trademark or registered trademark of their respective manufacturers. PO-1/96 Printed in USA