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Uart registers – Rainbow Electronics AT89C5131 User Manual

Page 86

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86

AT89C5131

4136A–USB–03/03

Example of computed value when X2 = 1, SMOD1 = 1, SPD = 1

Example of computed value when X2 = 0, SMOD1 = 0, SPD = 0

The baud rate generator can be used for mode 1 or 3 (refer to Figure 37.), but also for
mode 0 for UART, thanks to the bit SRC located in BDRCON register (Table 63.)

UART Registers

SADEN - Slave Address Mask Register for UART (B9h)

Reset Value = 0000 0000b

SADDR - Slave Address Register for UART (A9h)

Reset Value = 0000 0000b

SBUF - Serial Buffer Register for UART (99h)

Reset Value = XXXX XXXXb

Baud Rates

F

OSCA

= 16.384 MHz

F

OSCA

= 24 MHz

BRL

Error (%)

BRL

Error (%)

115200

247

1.23

243

0.16

57600

238

1.23

230

0.16

38400

229

1.23

217

0.16

28800

220

1.23

204

0.16

19200

203

0.63

178

0.16

9600

149

0.31

100

0.16

4800

43

1.23

-

-

Baud Rates

F

OSCA

= 16.384 MHz

F

OSCA

= 24 MHz

BRL

Error (%)

BRL

Error (%)

4800

247

1.23

243

0.16

2400

238

1.23

230

0.16

1200

220

1.23

202

3.55

600

185

0.16

152

0.16

7

6

5

4

3

2

1

0

7

6

5

4

3

2

1

0

7

6

5

4

3

2

1

0