tda9874aps NXP Semiconductors, tda9874aps Datasheet - Page 43

• Manufacturer Part Number: tda9874aps
• Description: Digital Tv Sound Demodulator/decoder
• Manufacturer: NXP Semiconductors

Philips Semiconductors
7.4
As a slave transmitter, the TDA9874A provides
12 registers with status information and data, a part of
which is for Philips internal purposes only. Each register is
accessed by means of a subaddress.
Detailed descriptions of the slave transmitter registers are
given in Sections 7.4.1 to 7.4.9.
Reading of data can start at any valid subaddress. It is
allowed to read more than 1 data byte per transmission
from the TDA9874A. In this case, the subaddress is
automatically incremented after each data byte, resulting
in reading the sequence of data bytes from successive
register locations, starting at SUBADDRESS.
Table 69 General format for reading data from the TDA9874A
Table 70 Explanation of Tables 69 and 71
Table 71 Format of a transmission using automatic incrementing of subaddresses
Note
1. n data bytes with auto-increment of subaddresses.
2000 Aug 04
S
S
SLAVE ADDRESS
0
A
SUBADDRESS
Sr
1
DATA
NAm
Am
P
S SLAVE ADDRESS 0 A SUBADDRESS A Sr SLAVE ADDRESS 1 A
Digital TV sound demodulator/decoder
SLAVE ADDRESS
Slave transmitter mode
BIT
0
START condition
7-bit device address
data direction bit (write to device)
acknowledge (by the slave)
address of register to read from
repeated START condition
data direction bit (read from device)
data byte read from register
not acknowledge (by the master)
acknowledge (by the master)
STOP condition
A
SUBADDRESS
43
A Sr SLAVE ADDRESS
Each data byte in a read sequence, except for the last one,
is acknowledged with Am. The subaddresses ‘wrap
around’ from decimal 255 to 0. If an attempt is made to
read from a non-existing subaddress, the device will send
a data pattern of all ones, i.e. FF in hexadecimal notation.
FUNCTION
DATA BYTE
Am
1 A
(1)
Product specification
DATA
TDA9874A
DATA NAm P
NAm
P