Product Data Sheets
LOW-going CE signal, at which point the current
address/mode levels are sampled and executed.
The two MSBs are on pins 9 and 10 for
each ISD1000A Series member.
OPERATIONAL MODES DESCRIPTION
The Operational Modes can be used in conjunc-
tion with a microcontroller, or they can be hard-
wired to provide the desired system operation.
M0 — Message Cueing
Message Cueing allows the user to skip through
messages, without knowing the actual physical
addresses of each message. Each CE LOW
pulse causes the internal address pointer to skip
to the next message. This mode should be used
for Playback only, and is typically used with the
M4 Operational Mode.
M1 — Delete EOM Markers
The M1 Operational Mode allows sequentially
recorded messages to be combined into a single
message with only one EOM marker set at the end
of the combined message. When this operational
mode is configured, messages recorded sequen-
tially are played back as one continuous mes-
M2 — Used for Cascading
During playback, EOM goes LOW at array over-
flow only. Normal EOM pulses are turned off.
M3 — Message Looping
The M3 Operational Mode allows for the auto-
matic, continuously repeated playback of the
message located at the beginning of the address
space. A message CANNOT completely fill the
ISD1000A device and loop.
M4 — Consecutive Addressing
During normal operations, the address pointer will
reset when a message is played through to an
EOM marker. The M4 Operational Mode inhibits
the address pointer reset on EOM, allowing mes-
sages to be played back consecutively.
M5 — CE Level Activated
The default mode for ISD1000A devices is for CE
to be edge-activated on Playback and level-acti-
vated on Record. The M5 Operational Mode
causes the CE pin to be interpreted as level-acti-
vated as opposed to edge-activated during Play-
back. This is specifically useful for terminating
Playback operations using the CE signal. In this
mode, CE LOW begins a Playback cycle at the
beginning of device memory.