tea5766uk NXP Semiconductors, tea5766uk Datasheet - Page 19

• Manufacturer Part Number: tea5766uk
• Description: Tea5766uk Stereo Fm Radio + Rds
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TEA5766UK_1
Product data sheet
8.2.1 Multiple interrupt events
8.2.2 Data available: DAVFLG
8.2.3 RDS synchronization: LSYNCFL
8.2 Interrupt flags and behavior
If the interrupt mask register bit is set then the setting of an interrupt flag for that bit
causes a hardware interrupt (INTX goes LOW). If the event occurs again before the flag is
cleared, then this does not trigger any further hardware interrupts until that specific flag is
cleared. However two different events can occur in sequence and generate a sequence of
hardware interrupts. Only when read, followed by a write of the INTMSK byte has been
done, a second interrupt can be generated, as the first interrupt blocks the input of the
INTX one-shot generator.
If subsequent interrupts occur within the INTX LOW period then these interrupts do not
cause the INTX period to extend beyond its specified maximum period. See also
Section
When a new block of data is received, the DAVFLG is set according to the diagrams
shown in
this continues for all subsequent received blocks (dependent on DAV mode) and in the
following situations:
The DAVFLG is reset by a read of BL[7:0] of RDSR2 (byte 15R) or BP[7:0] of RDSR3
(byte 17R). An interrupt is given each time when a new block of data is decoded and when
the DAVMSK is set; for details see
The SYNC bit, (see
is synchronized.
The action of the TEA5766UK depends on the status of the LSYNCMSK bit in
this is set then the loss of synchronization causes the LSYNCFL to go logic 1 and a
hardware interrupt is generated. The RDS part of the TEA5766UK is set to idle and waits
for the host processor to initiate a new synchronization search by setting the NWSY bit as
described in
•
•
•
•
•
During synchronization search in any DAV mode, if two valid blocks in the correct
sequence are received with BBC < BBL (synchronized)
During synchronization search in DAV-B mode if a valid A(C’)-block has been
detected; this mode can be used for fast search tuning (detection and comparison of
the Program Identification (PI) code contained in the A(C’)-block)
If the pre-processor is synchronized and in mode DAV-A or DAV-B a new block has
been processed
If the pre-processor is synchronized and in DAV-C mode two new blocks have been
processed
If the decoder is synchronized and for any DAV mode, with LSYNCMSK = 0, loss of
synchronization is detected (flywheel loss of synchronization, resulting in a restart of
synchronization search)
8.3,
Section 9
Figure
Table
26.
where the different DAV modes are described. Once synchronized,
8.
Table
Rev. 01 — 22 March 2007
22) shows the status of the RDS decoder. If it is set the decoder
Section
9.
TEA5766UK
Stereo FM radio + RDS
© NXP B.V. 2007. All rights reserved.
Table
18 of 59
8. If