80-0211-C Datasheet, PDF (6/12 Pages) List of Unclassifed Manufacturers – Speech And Music Processor

SC-691
Data sheet
Read Operation By The Master
The process for the read operation by the master is the same in either 4-bit or 8-bit mode. The read operation by
the master happens when the slave wants to send something to the master. The read process is initiated by the
slave by pulling OUTRDY_ low when it is ready.
The following events take place during the read operation:
The SC-691 puts the data to be sent to the master on the internal bus.
The SC-691 sets OUTRDY_ low to indicate that it is ready to send data to the microcontroller.
The microcontroller sets R/W_ high to indicate a read operation.
The microcontroller sets STROBE_ low. The data is available on the external data-bus at this point.
The microcontroller reads the data from the bus.
The microcontroller sets STROBE_ high. The SC-691 also pulls OUTRDY_ high at the rising edge of
STROBE_.
The data is taken from the external data-bus after STROBE_ goes high.
The microcontroller should latch or read in the data while STROBE is low. When the microcontroller sets
STROBE_ high, the SC-691 sets OUTRDY_ high to indicate that the data has been successfully transferred.
A) Sequence of events for a single read operation:
OUTRDY
R/W
STROBE
DATA
COMMAND/DATA
B) Read-Two speech data transfer sequences:
OUTRDY
R/W
STROBE
DATA
COMMAND/DATA
Figure 3: Data Transfer – Read
Write Operation By The Master
The process for the write operation by the master is the same in either 4-bit or 8-bit mode. The write operation
by the master happens when the slave is ready to request data or command from the master. The write process
is initiated by the slave by pulling INRDY_ low when the slave is ready to receive data. The following events
take place during the write operation:
The SC-691 sets INRDY_ low to indicate that it is ready to receive data from the microcontroller.
The microcontroller sets R/W _low to indicate a write operation.
The microcontroller puts the data in the external data-bus.
The microcontroller sets STROBE_ low after the data is valid.
The microcontroller sets STROBE_ high after a minimum of 300 ns. The SC-691 also pulls INRDY_ high at
the rising edge of STROBE_.
The data is latched in the SC-691 at the rising edge of STROBE_.
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P/N 80-0211-C
© 2003 Sensory Inc.