ISD1700A Datasheet, PDF (16/31 Pages) Winbond – Multi-Message Single-Chip Voice Record&Playback Devices

ISD1700A SERIES
• If the device is idle and the playback pointer is not currently pointing to the first or last
message:
o No message is erased.
o SE3, if present, will be played and the LED will flash twice.
o Play pointer will be unchanged.
• If the device is currently playing the first or last message, pressing ERASE will delete
the current message, as in the related cases described above.
b) Global Erase: Level-triggering this pin at Low for more than 2.5 seconds initiates the
Global Erase operation and deletes all messages, except the SEs. If SEs are present, the
device will play SE1 three times after ERASE is held for 2.5 seconds. If ERASE is not
released during the playback of SE1, all messages will be erased, and the chip will play
SE4. See Figure 7.1 for the operation details. The ERASE is debounced internally.
Triggering ERASE for individual erase during a record or forward operation is an illegal
operation and will be ignored. However, triggering ERASE for an individual erase operation
during playback will delete the current played message, if it is the first or last one.
ERASE key is Pressed and Held
Global Erase Starts here
2.5 seconds
Case 1 : Current messge location : 1st or Last
Erase 1st
or last
Play
SE2
message
Wait
Case 2 : Current messge location : Not at 1st or Last
Play
Wait
SE3
Global Play
Erase SE4
Play
Play
Play
SE1
SE1
SE1
Play SE1 3 times to Warn for
Glabal Erase to start.
Release ERASE key to abort the
operation
Global Play
Erase SE4
Play
Play
Play
SE1
SE1
SE1
Figure 7.1: Global Erase Operation
7.1.5 Reset Operation
A 0.1 µF capacitor is recommended to connect RESET to ground if a push button switch is
used on this pin. When RESET is triggered, the device will place both the record and the
playback pointers at the last message. When a microcontroller is used for a power-on-Reset,
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