TEF6730A_1 © NXP B.V. 2007. All rights reserved.
Product data sheet Rev. 01 — 21 February 2007 16 of 58
NXP Semiconductors
TEF6730A
Front-end for digital-IF car radio
8.2.1 Mode and subaddress byte for write
[1] When the write transmission of a state machine command starts during a mute state of the state machine,
the sequences of the state machine start immediately with the actions which follow the mute period in the
standard sequence (see Figure 9, Figure 11, Figure 13, Figure 15 and Figure 17).
[2] References to mute are only used for better understanding. Muting is performed in the IF DSP controlled by
the tuner AFHOLD and AFSAMPLE lines.
[3] In the modes preset and search the AM AGC time constant is set to fast during the period of complete
mute.
[4] The AF update sequence can also be started by pulling the AFHOLD pin LOW. In this case the AF
information should be loaded into the BUFFER before. LOW period for a correct AF update timing:
t
LOW
>20µs. Between the end of the I
2
C-bus transmission and the falling edge of the AFHOLD pulse a
delay of ≥ 20 µs is necessary.
Table 11. MSA - mode and subaddress byte bit allocation
7 6 5 4 3 2 1 0
MODE2 MODE1 MODE0 REGC SA3 SA2 SA1 SA0
Table 12. MSA - mode and subaddress byte bit description
Bit Symbol Description
7 to 5 MODE[2:0] mode; see
Table 13
4 REGC register mode
0 = buffer mode or back mode: previous tuning data is default for
new I
2
C-bus write (data of the BUFFER register is not changed
before I
2
C-bus write); see Figure 6
1 = control mode or current mode: current tuning data is default for
new I
2
C-bus write (the BUFFER register is loaded with CONTROL
register data before I
2
C-bus write); see Figure 7
3 to 0 SA[3:0] subaddress; write data byte subaddress 0 to 15. The subaddress
value is auto-incremented and will revert from SA = 15 to SA = 0. The
auto-increment function cannot be switched off.
Table 13. Tuning action modes
[1]
MODE2 MODE1 MODE0 Symbol Description
[2]
000bufferwrite BUFFER register, no state machine action, no
swap
0 0 1 preset tune to new program with 60 ms mute control; swap
[3]
;
see
Figure 8 and Figure 9
0 1 0 search tune to new program and stay muted (for release use
end mode); swap
[3]
; see Figure 10 and Figure 11
0 1 1 AF update tune to AF program; check AF quality and tune back
to main program; two swap operations
[4]
;
see
Figure 12 and Figure 13
1 0 0 jump tune to AF program in minimum time; swap;
see
Figure 14 and Figure 15
1 0 1 check tune to AF program and stay muted (for release use
end mode); swap; see
Figure 16 and Figure 17
1 1 0 load write CONTROL register via BUFFER; no state
machine action; immediate swap; see
Figure 6 and
Figure 7
1 1 1 end end action; release mute; no swap; see
Figure 18
