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TDA7546
Software specifications
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Table 48.
pllreg1 register
Table 49.
pllreg0 register
Note:
sinc4reg and testreg registers are dedicated for testing and are not described in this
specification.
Reset values of rds_qu, rds_corrp, rds_bd_h and rds_bd_l registers are not visible for the
programmer, because he can see only the copy of this registers in the RAM buffer after a
new RDS block was received.
The pllreg4-0 registers must be initialized first, before the RDS functionality can be used. If
the “PLLEN” bit of pllreg4 is set from zero to one, then the PLL will be initialized after
I
2
C/SPI transfer with the actual values of pllreg4-0. After the lock time the PLL switches
automatically over to the PLL output clock. The next I
2
C/SPI transfer is only allowed after the
lock time (500
μ
s) and additional 25 XTI input clock cycles. If the “PLLEN” bit is set from one
to zero, the PLL will be stopped and the system clock is switched back to the XTI input clock
(after the I
2
C/SPI transfer). The next I
2
C/SPI transfer is then only allowed after 25 XTI input
clock cycles. This is to avoid any I
2
C/SPI communication during clock switching.
The registers pllreg3-1 can be only changed at once. If there are less then all three pllreg3-
1 registers written during a I
2
C/SPI transfer, then they will be not updated.
If the XTI input frequency is 10.25MHz, then only register pllreg4 must be programmed,
because the pllreg3-0 register reset values can be used without any modification.
(10) Reset values are designed for 10.25 MHz XTI in-
put frequency.
(11) MF values smaller than 9 are ignored, 9 is then
used internally.
bit 8 of fractional factor (10) (12).
bit 9 of fractional factor (10) (12).
bit 10 of fractional factor (10) (12).
bit 11 of fractional factor (10) (12).
bit 12 of fractional factor (10) (12).
bit 13 of fractional factor (10) (12).
bit 0 of PLL multiplication factor (10) (11) (12).
bit 1 of PLL multiplication factor (10) (11) (12).
bit name
access
bit 7
bit 0
bit 1
bit 2
bit 3
bit 4
bit 5
bit 6
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
FRA8
FRA9
FRA12
MF1
FRA13
MF0
FRA11 FRA10
reset value
0
1
1
0
0
0
0
1
pllreg1
(12) The registers pllreg3, pllreg2 and pllreg1 must be
written at once to be updated, i.e. if the I2C/SPI stops
after pllreg2, then these registers are not updated.
bit 0 of fractional factor (10).
bit 1 of fractional factor (10).
bit 2 of fractional factor (10)
bit 3 of fractional factor (10).
bit 4 of fractional factor (10).
bit 5 of fractional factor (10).
bit 6 of fractional factor (10).
bit 7 of fractional factor (10).
bit name
access
bit 7
bit 0
bit 1
bit 2
bit 3
bit 4
bit 5
bit 6
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
FRA0
FRA1
FRA4
FRA7
FRA5
FRA6
FRA3
FRA2
reset value
0
1
0
0
0
0
0
0
pllreg0