9-20
DSP56367
MOTOROLA
Serial Host Interface
Characteristics Of The I
2
C Bus
•
Stop data transfer—The stop event is defined as a change in the state of the data line,
from low to high, while the clock is high (see Figure 9-8).
•
Data valid—The state of the data line represents valid data when, after a start event,
the data line is stable for the duration of the high period of the clock signal. The data
on the line may be changed during the low period of the clock signal. There is one
clock pulse per bit of data.
Figure 9-8 I
2
C Start and Stop Events
Each 8-bit word is followed by one acknowledge bit. This acknowledge bit is a high level put
on the bus by the transmitter when the master device generates an extra acknowledge-related
clock pulse. A slave receiver that is addressed must generate an acknowledge after each byte
is received. Also, a master receiver must generate an acknowledge after the reception of each
byte that has been clocked out of the slave transmitter. The acknowledging device must pull
down the SDA line during the acknowledge clock pulse so that the SDA line is stable low
during the high period of the acknowledge-related clock pulse (see Figure 9-9).
Figure 9-9 Acknowledgment on the I
2
C Bus
S
P
Start Event
Stop Event
SDA
SCL
AA0423
Start
Event
Clock Pulse For
Acknowledgment
S
1
2
8
9
SCL From
Master Device
Data Output
by Transmitter
Data Output
by Receiver
AA0424
Summary of Contents for DSP56367
Page 16: ...xvi MOTOROLA CONTENTS Paragraph Number Title Page Number ...
Page 22: ...xxii MOTOROLA List of Figures Figure Number Title Page Number ...
Page 26: ...xxvi MOTOROLA List of Tables Table Number Title Page Number ...
Page 148: ...4 6 DSP56367 MOTOROLA Design Considerations PLL Performance Issues ...
Page 248: ...9 30 DSP56367 MOTOROLA Serial Host Interface SHI Programming Considerations ...
Page 306: ...10 58 DSP56367 MOTOROLA Enhanced Serial Audio Interface ESAI ESAI Initialization Examples ...
Page 389: ...Bootstrap ROM Contents MOTOROLA DSP56367 A 15 end ...
Page 390: ...A 16 DSP56367 MOTOROLA Bootstrap ROM Contents ...
Page 432: ...C 8 DSP56367 MOTOROLA JTAG BSDL ...
Page 484: ...D 52 DSP56367 MOTOROLA Programmer s Reference ...
Page 490: ...E 6 DSP56367 MOTOROLA Power Consumption Benchmark ...
Page 516: ...F 26 DSP56367 MOTOROLA IBIS Model ...
Page 522: ...Index 6 MOTOROLA Index ...
Page 523: ......