D6351A Flash TAD Chip for an all Digital Telephone Answering Device with True FULL Duplex SpeakerPhone General Description The D6351A chip is a digital speech/signal processing subsystem that implements all functions of TRUESPEECH speech compression and voice prompts, telephone line signal processing, flash memory management, and True FULL Duplex SpeakerPhone for an all digital answering machine. The D6351A 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 D6351A DSP Speech Processor Host Controller Voice Prompt ROM Flash Memory Optional Figure 1. D6351A System Block Diagram Key Features n High-quality, variable low rate TRUESPEECH digital speech compression allowing 13-15 minutes of recording time per each 4 Mbit Flash Memory n Works with 4Mb or 16Mb Flash Memory Devices: Samsung KM29N040*, KM29N1600T** and KM29N16TS n Flexible storage of incoming messages (ICM) and outgoing messages (OGM), supporting multiple OGMs and multiple mailboxes n True FULL Duplex SpeakerPhone with both acoustical and near-end echo cancellation n TRUESPEECH natural-sound voice prompting for Day/Time stamp and voice instructions n DTMF generation and detection with near-end echo cancellation for superior performance n Programmable thresholds for VOX, DTMF, and Call Progress n Supports offset playback for jumps within a message n Easy Host software conversion from the D6305B n FLEXISPEECH variable speed, natural sound playback (50%-200%) n Simple 8-bit Host Interface n Low Power Consumption n Digital volume control *May have up to 3 bad sectors **May have up to 10 bad sectors A D6351A Device Configuration and System Components STANDARD COMPONENTS n D6351A-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 Samsung KM29N040 (44-pin TSOP II) 4Mb per device*, up to four devices per system n Samsung KM29N1600T (44-pin TSOP II) 16Mb, single device, or n Samsung KM29N16TS (44-pin TSOP II) 16Mb, single device * Optionally, the system will support a 32K or 64K x 8 EPROM/ROM (access time 300 ms or less) for Voice Prompt storage. This option is only available in systems with a single 4 Mbit flash memory device. 3 E D /C R RP 6 1 R D EL EL D A 0 C 9 8 7 7 C 6 7 4 7 1 0 D D D 3 7 1 R D 2 7 1 7 0 7 D A 7 6 D D A 8 6 R D D A 9 7 6 R D D A A 7 R D D D A 8 R R R A 9 1 1 D C V G 5 7 2 D R C N E E C C 3 1 D 0 1 S A 8 7 E/ A 6 6 5 6 6 ADDR15/CE2 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 D6351A-11 5 6 2 D X 0 2 1 D R 7 9 2 8 0 2 2 R D 0 N C 3 N C 2 1 3 3 N C C V 5 3 3 C G N D 4 3 N C N C 3 6 N C 3 7 LWF R 3 8 9 LRF D 3 3 0 4 1 0 C N Figure 2. D6351A-11 Pin Diagram B M M D B D A D6351A 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 is performed by the DSP subsystem which reports the status of the operation to the Host. All memory interface and management is 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. D6351A-11 n Speech Recording n Speech Playback n Memory / Message Management n DTMF and Tone Generation n DTMF Detection n Call Process Detection n Time / Date Stamping n Voice Prompts n Phone Number Storage n SpeakerPhone Functions Host Controller n Control the System n Read Buttons n Control Displays / Switches Figure 3. System Functions Simple Hardware Interface The hardware interface between the D6351A 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 D6351A, and the D6351A responds with status information. Once a command is issued, the D6351A will use the ACK pin to indicate that the status is available to be read. The hardware interface between the D6351A and Host is shown in Figure 4 below. 8051 D6351A-11 Port 0 RD WR HI/LO INT 8 HSTD0-7 HSTR HSTW HI/LO ACK Figure 4. D6351A / Host Interface Benefits of the D6351A n High-Quality, variable low rate TRUESPEECH digital speech compression allowing 13-15 minutes of recording time in only 4 Mbits of memory n Flash Memory support Allows use of readily available memory Reduces the system cost by eliminating the need for battery back-up in power failure situations Allows storage of voice prompts in Flash memory, eliminating the need for external ROM 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 n The Host-selectable thresholds for VOX, DTMF, and Call Progress detection makes for 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 professional sounding speakerphone to be added to your product with a very minimal additional cost © 1996 DSP Group, Inc. All rights reserved. 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-12/96 Printed in USA