Micronas SDA 6000, User Manual

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SDA 6000
PRELIMINARY DATA SHEET
Version 2.1
Peripherals
7 - 64 Micronas
7.3.3.2 Baud Rates in Synchronous Mode
For synchronous operation, the baud rate generator provides a clock with 4 times the
rate of the established baud rate (see
Figure 7-33 ).
Figure 7-33 ASC0 Baud Rate Generator Circuitry in Synchronous Mode
The baud rate for synchronous operation of serial channel ASC0 can be determined by
the formulas as shown in the following table.
S0BG represents the content of the reload register, taken as unsigned 13-bit integers.
The maximum baud rate that can be achieved in synchronous mode when using a CPU
clock of 33.33 MHz is 4.166 MBaud.
7.3.4 Autobaud Detection
The autobaud detection unit provides an ability to recognize the mode and the baud rate
of an asynchronous input signal at RXD. Generally, the baud rates to be recognized
should be known by the application. With this knowledge, a set of nine baud rates can
always be detected. The autobaud detection unit is not designed to calculate a baud rate
of an unknown asynchronous frame.
S0BRS S0BG Formula
0 0 … 8191
1
UES11152
13-Bit Reload Register
13-Bit Baud Rate Timer 4 ÷
f
BR DIV
f
3 ÷
2 ÷
MUX
S0BRS
S0R
33 MHz
f
BRT
Sample
Clock
S0BRS Selected Divider
1
0 ÷ 2
÷ 3
Shift/
8 x (S0BG+1)
Baud rate =
33 MHz
8 x Baud rate
33 MHz
S0BG =
- 1
12 x (S0BG+1)
Baud rate =
33 MHz
12 x Baud rate
33MHz
S0BG =
- 1