Texas Instruments MSP53C391, Руководство пользователя

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Master Microprocessor Interface Description
2-8
7) The master microprocessor pulses the STROB signal low and then high
to latch the data to the MSP53C391 input data latch.
8) A read operation should be performed just before each write operation to
ensure that the end-of-speech has not been reached.
If the EOS signal is asserted high during the read operation, the end-of-speech
has been reached and a reset operation should be performed prior to sending
new commands or speech data. The reset can be done in one of two ways:
Pulsing the INIT pin low and then waiting for the MSP53C391 to re-initialize
itself or by writing two dummy bytes as described the following.
RESET Operation
1) Perform a read operation to determine that the EOS signal is high.
2) If the EOS signal is high, write 2 bytes of dummy data to the MSP53C391
by repeating the write operation four times as described previously.
2.3.3 Method 3: Interrupt 2
This method is similar to method 2. The only difference is performing the read
operation is not necessary because the EOS and IRQ are available for direct
reads.
Figure 2–3. MSP53C391 Interfacing Diagram (Method 3: Interrupt 2)
Output Port
Output Port
Out Port
Out Port
Out Port
Out Port
Input Port
INT
STROB
R/W
INIT
DATA3
DATA2
DATA1
DATA0
EOS
IRQ
15
7
9
16
1
2
3
MASTER
MICROPROCESSOR MSP53C391
DAC+
DAC–
13
12
6
14
TO SPEAKER OR
AMPLIFIER/FILTER