Rainbow Electronics APR6016 - Manual (Page 12)

Preliminary
APR6016 Data Sheet
Page 12 Voice Recording & Playback Device
Revision 1.0
Recording Audio Data
When a SET_REC or REC command is issued the device will
begin sampling and storing the data present on ANAIN+ and
ANAIN- to the specified sector. After half the sector is used
the SAC pin will drop low to indicate that a new command can
be accepted. The device will accept commands as long as
the SAC pin remains low. Any command received after the
SAC returns high will be queued up and executed during the
next SAC cycle.
Figure 13 shows a typical timing diagram and OpCode
sequence for a recording operation. In this example the
SET_REC command begins recording at the specified mem-
ory location after T
arec
time has passed. Some time later the
low going edge on the SAC pin alerts the host processor that
the first sector is nearly full. The host processor responds by
issuing a
REC command before the SAC pin returns high.
The REC command instructs the APR6016 to continue
recording in the sector immediately following the current sec-
tor. When the first sector is full the device automatically jumps
to the next sector and returns the SAC signal to a high state
to indicate that the second sector is now being used. At this
point the host processor decides to issue a
STOP command
during the next SAC cycle. The device follows the STOP
command and terminates recording after TS
arec
.The /BUSY
pin indicates when actual recording is taking place.
Figure 13 Typical Recording Sequence
/CS
SCLK
DI
T
arec
TS
arec
SET_REC STOP
SAC
ANAIN+
ANAIN-
/BUSY
REC