SDA6000 Datasheet, PDF (220/380 Pages) Infineon Technologies AG – Teletext Decoder with Embedded 16-bit Controller

SDA 6000
Peripherals
Note: If the deviation of the baud rate after autobaud detection is too high, the baud rate
generator (fractional divider FDV and reload register BG) can be reprogrammed if
required to get a more precise baud rate with less error.
Non-Standard Baud Rates
Due to the relationship between Br0 to Br8 in Table 7-20 concerning the divide factor d_f
other baud rates than the standard ones can also be selected. For example, if a baud
rate of 50 kBaud has to be detected, Br2 is e.g. defined as baud rate for the 50 kBaud
detection. This further results in:
– f_DIV = 50 kBaud × d_f@Br2 = 50 kBaud × 192 = 9.6 MHz
Therefore, depending on the system clock frequency, the value of the fractional divider
(register FDV must be set according the formula in this example:
FDV = ^{512 x fDIV}
33 MHz
with f_DIV = 9.6 MHz
Using this selection (f_DIV = 9.6 MHz), the detectable baud rates start at 200 kBaud (Br0)
down to 1042 Baud (Br8). Table 7-22 shows the baud rate table for this example.
Table 7-22
Baud Rate
Numbering
Autobaud Detection using Non-Standard Baud Rates (f_DIV = 9.6 MHz)
Detectable
Non-Standard Baud
Divide Factor d_f
BG is Loaded after
Detection with Value
Rates
Br0
200.000 kBaud
48
Br1
100.000 kBaud
96
Br2
50 kBaud
192
Br3
33.333 kBaud
288
Br4
16.667 kBaud
576
Br5
8333 Baud
1152
Br6
4167 Baud
2304
Br7
2083 Baud
4608
Br8
1047 Baud
9216
2 = 002_H
5 = 005_H
11 = 00B_H
17 = 011_H
35 = 023_H
71 = 047_H
143 = 08F_H
287 = 11F_H
575 = 23F_H
7.3.4.3 Overwriting Registers on Successful Autobaud Detection
With a successful autobaud detection, some bits in register CON and BG are
automatically set to a value which corresponds to the mode and baud rate of the
detected serial frame conditions. In control register CON the mode control bits CON_M
Users Manual
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2000-06-15