sc16c751b NXP Semiconductors, sc16c751b Datasheet - Page 8

• Manufacturer Part Number: sc16c751b
• Description: 5 V, 3.3 V And 2.5 V Uart With 64-byte Fifos
• Manufacturer: NXP Semiconductors

NXP Semiconductors
SC16C751B_2
Product data sheet
The generator divides the input 16 clock by any divisor from 1 to (2
baud rates can be achieved by selecting the proper divisor values for the MSB and LSB
sections of baud rate generator.
Programming the baud rate generator registers DLM (MSB) and DLL (LSB) provides a
user capability for selecting the desired final baud rate. The example in
selectable baud rates when using a 1.8432 MHz crystal.
For custom baud rates, the divisor value can be calculated using
divisor in decimal
Table 5.
Using 1.8432 MHz crystal
Desired
baud rate
50
75
110
134.5
150
300
600
1200
1800
2000
2400
3600
4800
7200
9600
19200
38400
56000
Fig 3.
Crystal oscillator connection
Baud rates using 1.8432 MHz or 3.072 MHz crystal
Divisor for
16 clock
2304
1536
1047
857
768
384
192
96
64
58
48
32
24
16
12
6
3
2
=
Rev. 02 — 10 October 2008
XTAL1
XTAL1 clock frequency
--------------------------------------------------------------- -
1.8432 MHz
serial data rate 16
C1
22 pF
X1
Baud rate
error
0.026
0.058
0.69
2.86
XTAL2
C2
33 pF
5 V, 3.3 V and 2.5 V UART with 64-byte FIFOs
Using 3.072 MHz crystal
Desired
baud rate
50
75
110
134.5
150
300
600
1200
1800
2000
2400
3600
4800
7200
9600
19200
38400
XTAL1
1.8432 MHz
C1
22 pF
X1
XTAL2
Divisor for
16 clock
3840
2560
1745
1428
1280
640
320
160
107
96
80
53
40
27
20
10
5
002aaa870
1.5 k
C2
47 pF
SC16C751B
Equation
16
© NXP B.V. 2008. All rights reserved.
Table 5
1). Customized
1:
Baud rate
error
0.026
0.034
0.312
0.628
1.23
shows
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