SDA6000 Datasheet, PDF (219/380 Pages) Infineon Technologies AG – Teletext Decoder with Embedded 16-bit Controller

SDA 6000
Peripherals
Table 7-20 Autobaud Detection using Standard Baud Rates (f_DIV = 11.0592 MHz)
Baud Rate Detectable Standard Divide Factor d_f
Numbering Baud Rate
BG is Loaded after
Detection with Value
Br0
230.400 kBaud
48
Br1
115.200 kBaud
96
Br2
57.600 kBaud
192
Br3
38.400 kBaud
288
Br4
19.200 kBaud
576
Br5
9600 Baud
1152
Br6
4800 Baud
2304
Br7
2400 Baud
4608
Br8
1200 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
According to Table 7-20 a baud rate of 9600 Baud is achieved when register BG is
loaded with a value of 047_H, assuming that f_DIV has been set to 11.0592 MHz.
Table 7-20 also lists a divide factor d _f which is defined with the following formula:
baud rate = ^{f DIV}
d_f
This divide factor d_f defines a fixed relationship between the prescaler output frequency
f_DIV and the baud rate to be detected during the autobaud detection operation. This
means, that changing f_DIV results in a totally different baud rate table in terms of baud
rate values. For the baud rates to be detected, the following relations are always valid:
– Br0 = f_DIV/48_D, Br1 = f_DIV/96_D, … up to Br8 = f_DIV/9216_D,
A requirement for detecting standard baud rates up to 230.400 kBaud, is the f_DIV
minimum value of 11.0592 MHz. With the value FD_VALUE in register FDV, the
fractional divider f_DIV is adapted to the system clock frequency 33 MHz. Table 7-21
defines the deviation of the standard baud rates when using autobaud detection
depending on the system f_MOD.
Table 7-21
f_MOD
33 MHz
Standard Baud Rates - Deviations and Errors for Autobaud
Detection
FDV
172
Error in f_DIV
+ 0.24%
Users Manual
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2000-06-15