TVP5040 Datasheet, PDF (39/106 Pages) Texas Instruments – NTSC/PAL Digital Video Decoder With Macrovision Detection

2.7.6 I²C Microcode Read Operation
The data written during the microcode write operation can be read from the TVP5040 program RAM. During the read
cycle, the internal microprocessors program counter resets and points to location zero in the program RAM and
remains reset. Upon completion of the read operation, a microprocessor CLEAR-RESET operation is required. This
is performed by writing into the 7F register to clear reset and resume the microprocessor function. (There is no specific
data requirement to be written into the 7F register, any data resumes the microprocessor function.)
STEP 1
0
I2C Start (master)
S
STEP 2
I2C General address (master)
7
6
5
4
3
2
1
0
1
0
1
1
1
0
X
0
STEP 3
9
I2C Acknowledge (slave)
A
STEP 4
7
6
5
4
3
2
1
0
I2C Read register address (master)
1
0
0
0
1
1
1
0
Read address=8E
STEP 5
9
I2C Acknowledge (slave)
A
STEP 6
0
I2C Stop (master)
P
2.7.6.1 Read Phase 2:
STEP 7
0
I2C Start (master)
S
STEP 8
I2C General address (master)
7
6
5
4
3
2
1
0
1
0
1
1
1
0
X
1
STEP 9
7
I2C Acknowledge (slave)
A
STEP 10
I2C Read data (slave)
7
Data
6
Data
5
Data
4
Data
3
Data
2
Data
1
Data
0
Data
STEP 11
7
I2C Acknowledge (master)
A
Repeat STEP 10 and STEP 11 for all but the last byte read from program RAM.
STEP 12
I2C Read data (slave)
STEP 13
I2C Not acknowledge (master)
7
Data
9
A
6
Data
5
Data
4
Data
3
Data
2
Data
1
Data
0
Data
STEP 14
0
I2C Stop (master)
P
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