Philips SC28L91 User Manual
Page 26
Philips Semiconductors
Product data sheet
SC28L91
3.3 V or 5.0 V Universal Asynchronous
Receiver/Transmitter (UART)
2004 Oct 21
26
CSR CLOCK SELECT REGISTER
ББББ
ББББ
Addr
ББББББББББББББББ
ББББББББББББББББ
CSR (7:4)
ББББББББББББББББ
ББББББББББББББББ
CSR (3:0)
ББББ
ББББ
CSR
ББББББББББББББББ
ББББББББББББББББ
RECEIVER CLOCK SELECT
ББББББББББББББББ
ББББББББББББББББ
TRANSMITTER CLOCK SELECT
ББББ
ББББ
0x01
ББББББББББББББББ
ББББББББББББББББ
See Text and table 5
ББББББББББББББББ
ББББББББББББББББ
See Text and table 5
Table 5.
Baud rate (base on a 3.6864MHz crystal clock)
БББББ
БББББ
ББББББББББ
ББББББББББ
MR0[0] = 0 (Normal Mode)
БББББББББББ
БББББББББББ
MR0[0] = 1 (Extended Mode I)
БББББББББББ
БББББББББББ
MR0[2] = 1 (Extended Mode II)
БББББ
CSRA[7:4]
БББББ
ACR[7] = 0
ББББББ
ACR[7] = 1
ББББББ
ACR[7] = 0
ББББББ
ACR[7] = 1
ББББББ
ACR[7] = 0
ББББББ
ACR[7] = 1
0000
50
75
300
450
4,800
7,200
0001
110
110
110
110
880
880
0010
134.5
134.5
134.5
134.5
1,076
1,076
0011
200
150
1200
900
19.2K
14.4K
0100
300
300
1800
1800
28.8K
28.8K
0101
600
600
3600
3600
57.6K
57.6K
0110
1,200
1,200
7200
7,200
115.2K
115.2K
0111
1,050
2,000
1,050
2,000
1,050
2,000
1000
2,400
2,400
14.4K
14.4K
57.6K
57.6K
1001
4,800
4,800
28.8K
28.8K
4,800
4,800
1010
7,200
1,800
7,200
1,800
57.6K
14.4K
1011
9,600
9,600
57.6K
57.6K
9,600
9,600
1100
38.4K
19.2K
230.4K
115.2K
38.4K
19.2K
1101
Timer
Timer
Timer
Timer
Timer
Timer
1110
IP4–16X
IP4–16X
IP4–16X
IP4–16X
IP4–16X
IP4–16X
1111
IP4–1X
IP4–1X
IP4–1X
IP4–1X
IP4–1X
IP4–1X
NOTE:
1. The receiver clock is always a 16X clock except for CSR[7:4] = 1111. CSR[3:0]— Transmitter Clock Select. This field selects the baud rate
clock for the transmitter.
The field definition is as shown in Table 5, except as follows:
CSR[3:0]
1110
IP3 –16X
1111
IP3 –1X
The transmitter clock is always a 16X clock except for CSR[3:0] = 1111.
Table 6. Bit rate generator characteristics for Crystal or Clock = 3.6864MHz
ББББББББББББ
NORMAL RATE (BAUD)
БББББББББББ
ACTUAL 16X CLOCK (KHz)
БББББББББББББ
ERROR (%)
50
0.8
0
75
1.2
0
110
1.759
–0.069
134.5
2.153
0.059
150
2.4
0
200
3.2
0
300
4.8
0
600
9.6
0
1050
16.756
–0.260
1200
19.2
0
1800
28.8
0
2000
32.056
0.175
2400
38.4
0
4800
76.8
0
7200
115.2
0
9600
153.6
0
19.2K
307.2
0
38.4K
614.4
0
NOTE:
Duty cycle of 16X clock is 50%
1%