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Low Power Telephone Answering Device

ISD Part Number 101999RD5008

Low Power Telephone Answering Device
Version 1.0
ISD Part Number 101999RD5008
October 1999
ISD5008 TAD REFERENCE DESIGN DISTRIBUTION DISKETTE
There are 21 files on this diskette. The instructions provided on this page are also provided on the accompanying diskette in text format. The TAD2.ZIP file contains the following: · Tad2.DSN: the complete schematic in OrCAD Ver. 7.00 format. · Tad2.PPT: the complete schematic in MS PowerPoint format. · Tad2-bom.TXT: the parts BOM in text format. · Tad2-bom.XLS: the parts Bill of Materials in MS Excel format. · V10files.ZIP: the zipped copy of the firmware listings. This includes 14 files. Make sure that you have plenty of paper when you go to print as there are many pages in this file. · TAM2Guide.pdf: the Users Guide in Adobe PDF 4.0 format.
INSTALLATION INSTRUCTIONS TO ACCESS FILES
1. Verify that your hard drive has at least 4MB of free space to hold the files on this diskette. 2. Copy TAD2.ZIP onto your hard drive in a separate folder (directory). 3. Use WINZIP to open TAD2.ZIP then again to open V10FILES.ZIP. 4. Copy the .DSN file to your OrCAD project directory and print the schematics. If you do not have OrCAD Version 7.00 or higher, use the MS PowerPoint version of the schematics.
ISD Applications Department October 20, 1999 Please address all questions, via email, to chipcorder@isd.com.
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Low Power Telephone Answering System
INTRODUCTION .....................................................4 FEATURES.........................................................5 POWERING THE TAD2 ...............................................6 OPERATING THE TAD2 ...............................................6 TONE BETWEEN MESSAGES ..........................................8 POWER MANAGEMENT.............................................. 8 ELECTRICAL DESCRIPTION..........................................10 FIRMWARE CODE..................................................16 SOURCE CODE OVERVIEW ..........................................20 SCHEMATIC DIAGRAMS............................................. 21
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The ISD5008 solid state TAD contains not only basic answering machine features, but also offers the following additional features:
· One-way call record (phone number, direction, voice mail) · Two-way call record (complete conversions) · Private one-way message playback (while on a call) · Two-way message playback · Voice memo record and playback (phone in standby) · Private call screening · Personal outgoing message (given CID info) · Private call announce while on call (given CIDCW) · In-terminal answering machine · Storage of 8 minutes on single chip memory and an additional 12 minutes on the second chip · Battery power backup that can record incoming messages during power failures · LCD display for message status with support for caller ID
The TAD2 system is powered from either 4 AA cells or a 4-12 VDC wall adapter, capable of 150 mA, through a 3.1 mm connector. The center pin is ground.
All of the keypad operations are menu driven. At the base menu, the "Up" and "Down" keys scroll through submenus.
Main Menu
Displays the number of saved and new messages in the TAD.
Play Messages
The "Box" symbol button will start the play messages routine. If new messages exist, the oldest new message is played first. If no new messages exist, the TAD2 will display a message telling the user that no new messages exist. Selecting the "Left" arrow will play the oldest stored message. While a message is playing, the "Left" arrow rewinds, the "Box" will stop message playing, the "Right" arrow causes it to skip ahead to the next message and the "Up" and "Down" arrows adjust the volume. When the message has finished playing, the menu changes to the "Box", plays the message again, "Left" arrow plays the previous message, the "Right" arrow skips to the next message, the "Down" arrow deletes the message, and the "Up" arrow exits back to the main menu. After a message has finished playing and no user operations are requested for 15 seconds, the message routine will end and the menu goes back to the Main menu. During the time that the message is playing, the CID data is alternately displayed with the menu information.
Record Memo
Records a memo message (without CID Data) from the microphone. The "Box" starts and stops the recording.
Record OGM
Records the outgoing message that is to be played when the phone line is answered. The "Box" starts and stops the recording.
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Play OGM
Plays back the Outgoing message to the speaker.
Change Pass Code
Displays the currently set password. The "Left" and "Right" arrows move the cursor. The "Up" and "Down" arrows change the digit at the cursor location. The "Box" saves the password.
Phone Answering
The TAD2 will answer the phone after two rings. The outgoing message is played first. If the # key is not pressed during the outgoing message, a new message is recorded and saved. If the # key is pressed, the DTMF commands are executed. When the calling party hangs up, the recording is ended. The "Box" will also end the recording. If the slave phone is taken off-hook, the action that is currently taking place is immediately stopped and no message is saved.
DTMF Commands
When the "#" key is pressed while the outgoing message is played, the OGM is stopped. After the OGM has stopped, the user enters the pass code. If it is incorrectly entered, the TAD2 returns to the outgoing message after which the # can then be entered to try again. If the pass code is entered correctly, the oldest stored message begins playing. Three keys perform the following functions. The "1" key will back up ("rewind") the currently playing message. If the currently playing message is already at the beginning, the previous message will be played. The "2" key will save the currently playing message and the next message will begin playing. If the "3" key is pressed, the currently playing message will be deleted and then the next message will begin playing.
The next to the last row (1198) of the ISD5008 is played when the TAD2 interrupts (EOM or OVL) at the end of each message. There is a 1600 Hz tone recorded in the last two rows. Any desired audible indication could be recorded in these last two rows.
Power management is accomplished by using the two different power savings modes of the W78LE54 combined with the peripheral low power modes. The W91030 CID2 device, MT88L85 DTMF transceiver, ISD5008, and the ISD4004 all have sleep modes. The DAA, display, and the analog multiplex circuits are powered through PNP transistors and are turned off when not needed.
Doze Mode
Suspend Mode
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Upon resume the internal registers are restored from the settings that were saved during the suspend routine. After the resume has completed, the required action will then complete. I.e. menu function, ringing, etc.
Slave Suspend Mode
Anytime the slave phone is off-hook, the W91030 (together w / MT88L85 due to the economy of using a common crystal) is powered up while the remainder of the system is suspended. If a CAS tone is detected, the system is resumed. The line is captured by placing the DAA off-hook, energizing K1 to disconnect the slave phone, and then the CID data is captured. After this, K1 is de-energized and the DAA is placed onhook. The CID data is stored as well as displayed so that the user may switch-hook to answer the second call, if desired.
Figure 1: Block Figure of TAD2
16 X 2 LCD Display Switch Buffer Control Switches 1 of 8 Decode Latch Switch Switch Data W78LE54 CPU Switch Switch DTMF Tranceiver In Out W91030 CID2 AUXIN ISD4004 ISD5008 AUXOUT In
ANAOUT
Current Sense NC Relay Differential In
Phone
Ring Audio In Audio Out MIC Mux DAA Line
ANAIN
Microphone
Speaker
Power Supply
Digital Circuitry
U15 W78LE54 Microcontroller The Winbond W78LE54 microcontroller contains 16K of code EEPROM, 256 bytes of data RAM, three timers, a UART, four I / O ports and a serial port.
Port 0 Port 0 is shared between U11 74HC574 8-bit latch, U12 MT88L85AN - DTMF transceiver, U10 74HC245, U5 ISD5008, and U8 ISD4004. The port drives the input of the latch. Port 0, bits 0.6 are used to communicate with the DTMF transceiver. The buffer interfaces with the display. Bits 5.6 are used for data in and data out to the ISD components.
0 1 2 3 4 5 6 7 DTMF Q1. DTMF Q2. DTMF Q3. DTMF Q4. DTMF DS. DTMF R / W - ISD MISO. DTMF RS0 - ISD MOSI. Unused. Latch / buffer - D1 input. Latch / buffer - D2 input. Latch / buffer - D3 input. Latch / buffer - D4 input. Latch / buffer - D5 input. Latch / buffer - D6 input. Latch / buffer - D7 input. Latch / buffer - D8 input.
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The 74HC574 is an 8-bit latch that drives several control signals:
The 74HC138 is a 1 of 8 decoder. The outputs are used for chip selects and to select the switch inputs.
Port 1 Port 1 is used as follows:
Port 2 Port 2 is used as follows:
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Port 3 Port 3 is used as follows:
U17 24LC64 NVRAM The 24LC64 NVRAM is an industry standard 64K (8K bytes) with an I2C 2 wire interface. The interface is implemented through Port 1 bits 2.3. The firmware auto-detects the RAM size. The NVRAM is used to store message mappings and CID data. It retains this data during power outages or while changing the batteries.
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Analog Circuitry
DAA The DAA is implemented discretely with U3A, U3B, U3C, LMC6484 Op amp, U4 CP Clare ITC117P integrated function device, and T1. Isolation and ringer U4 contains an opto-isolated relay, diode bridge, Darlington transistor, and ring detector. The Darlington is configured as a shunt regulator to allow for the use of a dry (no DC current) transformer. T1 is AC coupled to the phone line through the U4 relay. The ring signal is coupled through R5, C1, D3 and D4 into dual LEDs in U4. 2 Wire to 4 Wire Converter U3C supplies a reference voltage while U3A and U3B are configured as a 2 wire to 4 wire converters. The secondary of T1 is DC coupled to the converter. One side of the secondary is supplied with the reference voltage. The other is driven through R28. U3B is configured as both an inverting and non-inverting amplifier. U3B is an inverting amplifier to the received signal and a non-inverting amplifier to the transmitted signal. The signals are summed at the tie point of T1 and R28. The result is that the transmitted signal output by U3B is a minimum of 10 dB below the received signal. Above approximately 400 Hz it is 20 dB below from the receive signal.
The firmware uses and maintains variables and data to manage the storing and playback of messages in the ISD5008 and ISD4004. The TAD2 uses a Message Address Table (MAT) as described in ISD Application Notes combined with a variation on the actual structure. Two actual tables are maintained within the NVRAM. One stores all CID data. The other stores the actual audio message table combined with a status byte and a pointer into the CID table if the message is linked to a CID message.
NVRAM
The TAD2 has an NVRAM that is used to store all volatile data and tables. The NVRAM is an industry standard 24LC64 with a two wire I2C interface. The NVRAM manipulation is performed on a block basis with a maximum of 32 bytes per transfer.
Message Address Table Structure
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Tags Below is a list of tag definitions:
MatTag.
Beginning of message string. The MatTag is followed by the MATLength. The message string is length bytes long plus 3 MatTag, length byte, and MATEnd. Beginning of CID pointer field. The CidTag data is an integer offset into the CID table to the CID message with this audio message. If no CID message is associated with the audio message, the CidTag is not in the message string. The CidTag, if it exists, is followed by the CIDLength (always 2), and then one byte that is the CID message number in the CID message table. Beginning of audio message string. The MesTag precedes the actual audio block map of the message. It is followed by the MesLength. The MesString is MesLength long. See Audio Blocks section for a definition of the actual audio block data. End of the Message address table for this message. The Tag is always followed by another MatTag or the TableEnd tag. End of message table. There are no more audio messages.
CidTag.
MesTag.
MatEnd.
TableEnd
Audio Message Blocks Each of the ISD devices is divided into 128 audio blocks. Each ISD5008 audio block consists of 9 consecutive rows. Each ISD4004 audio block consists of 18 consecutive rows. The length of time for each row varies depending upon the sample rate. Block0 to Block127 (0h.07fh) point to the ISD5008 while Block128 to Block255 (080h.0ffh) point to the ISD4004.
Message Status The message status byte follows the StatTag and StatLen bytes in the Message Table.
Status. New Message - Set for New, Clear for message has been played. OGM -this message is the OGM message. X 7 6 5 4 3 2 1 0 X
Used Block Table
NVRAM Map
NVRAM Byte Address 0x00.0x0f Name. Description.
RootBlock
The root block is 16 bytes long. It holds the firmware version string and some variables needed at power up. The used block table block is 32 bytes long. It holds an image of the Used Block Table in case of power fail. The audio message table holds the message table for all audio messages. The CID message table holds the CID messages.
0x10 . 0x2f
UBTBlock
0x30 . 0x17ff
AudioMessageTableBlock
0x1800 . 0x1fff
CIDMessageTableBlock
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Maximum audio message store capability
Almost 6 Kbytes of the NVRAM are assigned to the audio MAT. The actual number of audio messages that can be stored varies depending upon the number of audio blocks used within each message and the maximum available NVRAM storage. One message can be of any length limited only by available audio storage. The minimum length of the audio message is 11 bytes for a one block audio message with a CidTag field.
MatTag + MatStatus + MatLength + CIDTag + CIDLength + CIDData + MesTag + MesLength + MesData + EndTag. 1 1 2 1 1 1 1 1 1 1
CID Table 2048 bytes of the NVRAM are allocated to store CID messages. Please refer to the MatTag, MatLength, MsgEnd, and MatEnd tags above for the definitions. A message combines these tags with the actual CID message received. The pointer store in the audio MAT is the sequential message number in the CID table. The length of each CID message varies. Using an average CID message length of 48, the Tad2 is capable of storing 41 CID messages. Note that this is a minimum and will vary depending upon how many no name or no number messages are stored.
The firmware provided with the TAD2 is compiled using seven source code files and their companion include (.h) files. A general description is below while a detailed description is contained in the h files included with the source code zip file.
Tad2.c
Tad2 contains the main program loop. This is where the menu commands are located. All other procedures are called from this file.
Tadio.c
Tadio contains all of the hardware implementation specific routines. These procedures are called by the other routines when hardware related functions are needed. The actual I / O map is also defined here.
NVRam.c
The NVRAM related procedures are contained in this module. All NVRAM reads and writes are performed in this module.
ISD.c
ISD contains the command processor for the ISD devices. The interrupt routines for ISD operations are also here.
Mesman.c
The Message address table procedures are in the module. All routines for creating and retrieving audio messages are here. The ISD command processor makes calls to this module to obtain audio related data needed to execute the desired command.
Cid.c
The caller ID routines are located in this module.
Display.c
The display routines are located in this module.
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P1 CENTER PIN IS GROUND. 1 PJ-007 2 D2
3.0 VDC Regulator Digital VCC
VCC3 U2 8 IN SHDN BEAD 5 C5 100uF LT1521-3 R12 BAT
MBRS340T3 D1 MBRS340T3
SCHEMATIC DIAGRAMS
VCC3 BT1 BATTERY R54 10K R55 Q5 MMBTA55L R51 270K R53 100K C6 22uF 2.2K
Figure 2: Power Schematic
1 3.0V 2 SENSE 3 GND 6 GND 7 GND VA R13 0
C42 10uF
Analog VCC
C12 10uF
DISPWR
Display VCC
C27 .1uF D12 SD103 R52 100K C19 2.2uF SD103 ~-2.-3VDC DISBIA
Q DIS THR TR LMC555 C28 .001uF 2 6 7
Display Bias
Switched Analog VCC (Mic. & ISD5008 input mux)
Note: This diagram is available on the accompanying disk as power.sch.
Q3 MMBTA55L
FSKEN 358PDN CIDMUT MICEN
D0 D1 D2 D3 D4 D5 D6 D7 D1 D2 D3 D4 D5 D6 D7 D8 CLK OC VCC3 Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8
OUTEN
74HC574 A B C
Voltage Monitor / Reset Timeout
100K MN13822-H R68 100K C39 .1uF G1 G2A G2B
74HC138
Chip Selects
0h - DTMF 1h- ISD4004 2h - ISD5008 3.7h - Switches
Figure 3: Digital Schematic
P0.0 P0.1 P0.2 P0.3 P0.4 P0.5 P0.6 P0.7
1 2 3 4 5 6 7 8 P1.0 P1.1 P1.2 P1.3 P1.4 P1.5 P1.6 P1.7 P3.0 / RXD P3.1 / TXD P3.2 / INT0 P3.3 / INT1 P3.4 / T0 P3.5 / T1 P3.6 / WR P3.7 / RD 10 11 12 13 14 15 16 17 29 30
VCC3 PSEN ALE / P W78LE54 R70 1K C45 .1uF
VCC3 C38 .1uF C40 .1uF C37 .1uF
Winbond W78LE54 256Bytes RAM 8KBytes EEROM
GND VCC
NVRAM 8KByte
C41 TONIN .1uF R64 51K
U12 1 2 R63 51K Y1 3.58 MHZ 3 4 6 IN+ INGS VREF OSC1 7 ST / GT EST 22
R62 10K
U17 24LC64
R45 60.4K C25 .1uF
R46 53.6K
CIDA+ CIDA464K R44
358CLK
1 2 3 4 10 IN+ INGCFB VREF OSC1
358CLK
OSC2 C34
R60 10K
TONE C36 39pF C35 .1uF 39pF
Q1 Q2 Q3 Q4 CS DS R / W RS0 PWDN IRQ
Note: This diagram is available on the accompanying disk as digital.sch.
11 6 7 8 OSC2 RNGDI RINGRC RINGON DCLK DATA DR CD INT SLEEP FSKE MODE ALGO ALGRC ALGR CAP R49 825K C23 .1uF R48 226K 16 17 18 19 20 14 15 9 21 22 23 5
GND2 GND1 13 12
DTMF Transceiver
Winbond W91030 CID Decoder, Ring Detect, CAS VCC3 Detect
W91030 R59 150K RING
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C32 .22uF
Enable Reset Latch from CPU
Reset on Ringing Reset Latch
Reset on Slave Phone going Off-Hook
OHK 1 4.7K
Reset on Switch Closure
S0 SD103 D20 DISPWR SD103 D15 SD103 S2 C20 22uF D21 SW SD103 S1 D17 SW D16 S0
Switches
SD103 D18 SD103 D23 SD103 D0.7 SD103 D24 SW SD103 S5 D19 SW SD103 S3
D14 SW
Figure 4: Display / Keyboard Schematic
Switch Selects
Display Latch
D7 D6 D5 D4 D3 D2 D1 D0 12 13 14 15 16 17 18 19 VCC3
LCD Display
VCC 20
DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 E R / W RS VEE VCC VSS DMC-16249
DISE DISRS DISBIA
Contrast Control
Size Document Number Rev
Date:
D0.7 VCC3 C29 47uF VA VCC3 C24 22uF
C18 R41 13 AUDOUT ANA+ ANAAMCAP ISD4004 17 16 14 R57 10K 10K
.1uF VCC3 VA
MISO MOSI SCLK SS RAC INT XCLK
VCCD VSSD VSSA VCCA VSSA VSSA
C33 .1uF R56 10K
C11 47uF C22 22uF U5 C30 .1uF DAAIN J3 2 3 1 C31 .1uF VAS
ISD4004
Figure 5: 5008 Schematic
R31 1.5K
VCCA VCCD VCCD
AUXOUT ANAOUT+ ANAOUTSP+ SPN / C N / C N / C 7 21 22 16 14 11 12 20
4 3 1 2 24 25 26 MISO MOSI SCLK SS RAC INT XCLK
C9 220uF
100 Ohm Speaker
CUI MJ-3536
ISD5008
VSSA VSSA VSSA VSSD VSSD
WM-54B MICAMCAP ISD5008 C21 4.7uF
C17 10 13
R33 1.5K
U6B CD4066BC 10
MICEN
ISD5008 Input Mux
U6D CD4066BC 9
DAAOUT VAS
R39 4.7K R40 100K X1
1 Q6 0TIE
Note: This diagram is available on the accompanying disk as 5008.sch.
MMBTA05L 4 U6C CD4066BC 3
Size Document Number Rev
Date:
990601-05 ISD5008.SCH Tuesday, October 12, 1999
Sheet
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VCC3 D5 SD103 R43 VCC3 D6 SD103 D9 SD103 34K CIDA+
CID Differential Input
R47 CIDAVCC3 VCC3 R2 100K OHK Q1 MMBTA05L
D10 SD103 R35 619K R34 619K R1 100K
U1 LDA110 Line Current Detect J2
Figure 6: DAA Schematic
Slave Phone Mute Relay
R36 360 R3 CIDMUT 2.2K 1 Q2 MMBTA05L
C15 10UF
6 5 4 Slave Phone 3 2 1 RJ11
Switched VCC for DAA and Off-Hook
R5 8.2K
6 5 Telephone Line 4 3 2 1 RJ11
Receive Amp
TONIN C7 DAAOUT .1uF LMC6484AIM 51K R20 D8 3.2V 6 R14 27K 7 + 5 U3B
Integrated Telephone Circuit Relay, Diode Bridge, Darlington Ring Voltage Detect
R15 51K
R16 464K
C8 10uF
10 + 8 LMC6484AIM 34K R23 51K D7 3.2V R28 620 R25 51K 51K R24 3 U3A 1 LMC6484AIM 4 T1 2 -
DAA Reference Voltage
34K R8
Note: This diagram is available on the accompanying disk as daa.sch.
C4 .1uF
C10 DAAIN .1uF R26
1 TRANSFORMER
Dry Transformer
Transmit Amp
R22 51K
Size Document Number Rev
Date:
990601-06 DAA.SCH Wednesday, October 13, 1999 Sheet 5
2727 North First Street San Jose, California 95134 Tel: 408 / 943-6666 Fax: 408 / 544-1787 http://www.isd.com
Part No. 101999RD5008