Single-Chip Voice Recording & Playback Device for Multiple 40- to 60-Second Messages

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Function Description of Playback in Tape Mode using

Auto Rewind Option

On power-up, the device is ready to record or play back,

starting at the first address in the memory array. Before you

can begin playback, the /CE input must be set to low to

enable the device and /RE must be set to high to disable

recording and enable playback. The first high to low going

pulse of the /M1_Message pin initiates playback from the

beginning of the current message; on power up the first mes-

sage is the current message. When the /M1_Message pin

pulses low the second time, playback of the current message

stops immediately. When the /M1_Message pin pulses low a

third time, playback of the current message starts again from

its beginning. If you hold the /M1_Message pin low continu-

ously the same message will play continuously in a looping

fashion. A 1,530 ms period of silence is inserted during loop-

ing as an indicator to the user of the transition between the

beginning and end of the message.

Note that in auto rewind mode the device always rewinds to

the beginning of the current message. To listen to a subse-

quent message the device must be fast forwarded past the

current message to the next message. This function is

accomplished by toggling the /M2_Next pin from high to low.

The pulse must be low for least 400 cycles of the sampling

clock. After the device is incremented to the desired message

the user can initiate playback of the message with the play-

back sequence described above. A special case exists when

the /M2_Next pin goes low during playback. Playback of the

current message will stop, the device will beep, advance to

the next message and initiate playback of the next message.

(Note that if /M2_Next goes low when not in playback mode,

the device will prepare to play the next message, but will not

actually initiate playback).

If the /CE pin goes low during playback, playback of the cur-

rent message will stop, the device will beep, reset to the

beginning of the first message, and wait for a subsequent

playback command.

When you reach the end of the memory array, any subse-

quent pulsing of /M1_Message or /M2_Next will only result in

a double beep. To proceed from this state the user must

rewind the device to the beginning of the memory array. This

can be accomplished by toggling the /CE pin low or cycling

power.

Functional Description of Recording in Tape Mode using

On power-up, the device is ready to record or play back,

starting at the first address in the memory array. Before you

can begin recording, the /CE input must be set to low to

enable the device and /RE must be set to low to enable

recording. On a falling edge of the /M1_Message pin the

device will beep once and initiate recording. A subsequent

rising edge on the /M1_Message pin will stop recording and

insert a single beep. If the /M1_Message pin is held low

beyond the end of the available memory, recording stops

automatically, and two beeps are inserted; regardless of the

state of the /M1_Message pin. The device returns to the

standby mode when the /M1_Message pin is returned high.

A subsequent falling edge on the /M1_Message pin starts a

new record operation in the memory array immediately fol-

lowing the last recorded message, thus preserving the last

recorded message.

To record over all previous messages you must pulse the /CE

pin low once to reset the device to the beginning of the first

message. You can then initiate a record sequence, as

described above, to record a new message. The most

recently recorded message will become the last recorded

message and all previously recorded messages following this

message will become inaccessible.

If you wish to preserve any current messages it is recom-

mend that Auto Rewind option be used instead of Normal

option. If Normal option is necessary the following sequence

can be used. To preserve current messages you must fast

forward past the messages you want to keep before you can

record a new message. To fast forward when using the Nor-

mal option you must switch to play mode and listen to mes-

sages sequentially until you arrive at the beginning of the

message you wish to overwrite. At this stage you should

switch back to record mode and overwrite the desired mes-

sage. The most recently recorded message will become the

last recorded message and all previously recorded messages

following this message will become inaccessible. All inputs,

except /CE are ignored during recording.

Functional Description of Playback in Tape Mode using

On power-up, or after a low to high transition on /RE the

device is ready to record or play back starting at the first

address in the memory array. Before you can begin playback

of messages, the /CE input must be set to low to enable the

device and /RE must be set to high to enable playback. The

first high to low going pulse of the /M1_Message pin initiates

playback from the beginning of the current message. When

the /M1_Message pin pulses from high to low a second time,

playback of the current message stops immediately. When

the /M1_Message pin pulses from high to low a third time,

playback of the next message starts again from the begin-

ning. If you hold the /M1_Message pin low continuously, the

current message and subsequent messages play until the

one of the following conditions is met: the end of the memory

array is

reached, the last message is

reached, the

/M1_message pin is released. If the last recorded message

has

already

played,

any

further

transitions

on

the

/M1_Message pin will initiate a double beep for warning and

the /M7_END pin will go low. To exit this state you must pulse

the /CE pin low once during standby to reset the pointer to

the beginning of the first message.

APR9600

APLUS

the Normal Option

Auto Rewind Option