STV0119A datasheet(21/42 Pages) STMICROELECTRONICS

21 / 42 page

-80

-70

-60

-50

-40

-30

-20

-10

(x106) (Hz)

Figure 29 : Logarithmic PSD Scale

IV - FUNCTIONAL DESCRIPTION (continued)

IV.16 - I

2C Bus

An external micro-controller controls the STV0119A

via an I

2C busby writing into or readingfrom internal

registers. The I

2C interface supports the ”fast

2C protocol”(up to 400kHz - and potentially more).

The default I

2C addresses of the STV0119A are :

- in write mode : ”01000000” (40 hex)

- in read mode : ”01000001” (41 hex)

After a hardware reset, it is these addresses that

the STV0119A recognizes.

It is possible to modify the default I

2C address by

tiing the TTXS/CSI2C pin to logic ‘1’ and validat-

ing the change by writing into a dedicated bit in

In that case, the STV0119Ahas a newI

2C address:

- in write mode : ”01000010” (42 hex)

- in read mode : ”01000011”(43 hex)

Once the I

2C addresshas been changed, it cannot

be modifed anymore until the next hardware reset.

Note that these I

2C addresses are the same as

those used by the STV0117/STV0117A (others

ST PAL/NTSC Digital Encoder).

It is expected that I

2C address changes will nor-

mally be needed for dual encoding applications.

The exact procedure to change the I

2C addresses

is detailed below, in the section that deals with dual

encoding applications.

Write and read operations are described in Fig-

ures 30 and 31.

SCL

SDA

R/W

I2 C Slave Address 40h

ACK by

STV0119

LSB Address

Start

Data Byte 2

Data Byte 3

Data Byte n

Stop

SCL

SDA

Data Byte 1

ACK by

STV0119

ACK by

STV0119

ACK by

STV0119

ACK by

STV0119

ACK by

STV0119

Figure 30 : I

2C Write Operation (default address at power-on, CSI2C

≠ ’1’)

SCL

SDA

R/W

I2C Slave Address 40h

LSB Address

Start

SCL

SDA

R/W

D 0

Data Byte n

Start

D 7

Stop

Data Byte 1

I2C Slave Address 41h

Stop

ACK by

STV0119

ACK by

STV0119

ACK by

micro

ACK by

STV0119

ACK by

micro

Figure 31 : I

2C Read Operation (default address at power-on, CSI2C

≠ ’1’)

STV0119A

21/42

STV0119A датащи(PDF) 21 Page - STMicroelectronics

STV0119A датащи(HTML) 21 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42

датащи скачать

ссылки URL