Philips Semiconductors
Product specification
RDS/RBDS pre-processor
SAA6588
I2C-BUS INTERFACE REGISTERS
Table 2 Output registers
The I2C-bus interface is connected to other blocks of the
pre-processor via internal registers (byte oriented). Those
can either be written by the pre-processor control and read
by the main controller I2C-bus or vice versa.
DATA
FUNCTION
Byte 0R
Byte 1R
Byte 2R
Byte 3R
Byte 4R
decoder and data status information;
see Table 12
last processed block (HIGH byte);
see Table 15
The device provides 3 input control registers to which may
be written via the I2C-bus and 7 output registers which
may be read via the I2C-bus.
last processed block (LOW byte);
see Table 15
The decoder control updates the output registers after the
detection of a new RDS/RBDS information block and
reads the new mode control settings of the input control
registers. Both operations may occur in the same time slot,
provided that the read operation is complete before a new
RDS/RBDS data bit is processed by the demodulator.
previously processed block (HIGH byte);
see Table 15
previously processed block (LOW byte);
see Table 15
Byte 5R
Byte 6R
error status information; see Table 15
signal quality indication; see Table 15
For the corresponding access the registers are addressed
by two separate register pointers, write-enable and
read-enable signals, which are activated either via the
decoder control or via the I2C-bus interface control.
WRITE TRANSMISSION FORMAT
Table 3 Description of initialization and mode control
byte (byte 0W)
During a read or write transmission from the I2C-bus the
read/write pointer selects the register of the first byte for
transmission and is auto-incremented by the I2C-bus
control for the transfer of subsequent bytes.
BIT NAME
FUNCTION
7
SQCM 0: triggered signal quality measurement
1: signal quality continuous measurement
TSQD 0: no determination of signal quality
During a write transmission after reception of the device
slave address and write bit, the mode control settings for
the pre-processor have to be send in the protocol
sequence as shown in Table 1 and Fig.5.
6
1: trigger of signal quality detector
measurement
5
NWSY 0: normal processing mode
1: restart of synchronization
During a read cycle after reception of the device slave
address and read bit the requested RDS/RBDS data has
to be received in the protocol sequence as given in Table 2
and Fig.7.
4
3
2
SYM1 selection of error correction mode for
synchronization search; see Table 4
SYM0
RBDS 0: RDS processing mode
1: RBDS processing mode
Table 1 Input control registers
DATA
FUNCTION
1
0
DAC1 selection of data output protocol and
Byte 0W
initialization and mode control setting;
see Table 3
indirectly control of data available output
signal (DAVN); see Table 5
DAC0
Byte 1W
Byte 2W
pause level and flywheel setting;
see Table 6
pause time/oscillator frequency and
quality detector sensitivity setting;
see Table 7
1997 Sep 01
11
NXP [ NXP ]
