ox16cf950 ETC-unknow, ox16cf950 Datasheet - Page 39

• Manufacturer Part Number: ox16cf950
• Description: Cost Asynchronous Card
• Manufacturer: ETC-unknow

The use of TCR does not require the device to be in 650 or
950 mode although only drivers that have been written to
take advantage of the 950 mode features will be able to
access this register. Writing 0x01 to the TCR will not switch
6.10.4 Input Clock Options
A system clock must be applied to XTLI pin on the device.
The speed of this clock determines the maximum baud rate
at which the device can receive and transmit serial data.
This maximu m is equal to one sixteenth of the frequency of
the system clock (Increasing to one quarter of this value if
TCR=4 is used).
OXFORD SEMICONDUCTOR LTD.
Table 33: TCR Sample Clock Configuration
0000 to 0011
0100 to 1111
Sampling
TCR[3:0]
Clock
16
15
14
13
12
11
10
9
8
7
6
5
4
Frequency
14.7456
60.000*
1.8432
7.3728
18.432
32.000
33.000
40.000
50.000
Clock
(MHz)
Value
0x0F
0x0E
0x0D
0x0C
0x0B
0x0A
0x00
0x09
0x08
0x07
0x06
0x05
0x04
TCR
Table 35: Maximum Baud Rates Available at all ‘TCR’ Sampling Clock Values
Table 34: Example clock options and their assosiacted maximum baud rates
115,200
122,880
131,657
141,785
153,600
167,564
184,320
204,800
230,400
263,314 1,053,143 2,106,514 2,633,143 4,571,429 5,714,286 7,142,857 8,571428
307,200 1,228,667 2,457,600 3,072,000 5,333,333 6,666,667 8,333,333
368,640 1,474,400 2,949,120 3,686,400
460,800 1,843,000 3,686,400 4,608,000
1.8432
0xAE (21.750)
0xD9 (27.125)
0xFF (31.875)
0x50 (10.000)
0x8F (17.875)
0x8B(17.375)
0x08 (1.000)
0x80 (8.000)
0x20(4.000)
CPR value
Clock cycles per bit
460,750
491,467
526,571 1,053,257 1,316,571 2,285,714 2,857,143 3,571,429 4,285,714
567,077 1,134,277 1,417,846 2,461,538 3,076,923 3,846,154 4,615,384
614,333 1,228,800 1,536,000 2,666,667 3,333,333 4,166,667
670,182 1,340,509 1,675,636 2,909,091 3,636,364 4,545,455 5,454545
737,200 1,474,560 1,843,200
819,111 1,638,400 2,048,000 3,555,556 4,444,444 5,555,556 6,666,667
921,500 1,843,200 2,304,000
4-15
16
7.372
frequency
Effective
crystal
1.8432
1.8432
1.8432
1.8432
1.8417
1.8462
1.8391
1.8433
1.8824
921,600
983,040 1,228,800 2,133,333 2,666,667 3,333,333
14.7456
1.8432MHz
Error from
System Clock (MHz)
1.152M
0.00
0.00
0.00
0.00
0.08
0.16
0.22
0.01
2.13
18.432
(%)
the device into 1x isochronous mode, this is explained in
the following section. (TCR has no effect in isochronous
mode). If 0x01, 0x10 or 0x11 is written to TCR the device
will operate in 16x mode.
Reading TCR will always return the last value that was
written to it irrespective of mode of operation.
The industry standard system clock for PC COM ports is
1.8432 MHz, limiting the maximum baud rate to 115.2
Kbps. The OXCF950 supports system clocks up to 60MHz
at 5V or 50 MHz at 3.3V and its flexible baud rate
generation hardware means that almost any frequency can
be optionally scaled down for compatibility with standard
devices.
Max. Baud rate
with CPR = 1,
2.00M
3.20M
4.00M
6.40M
8.00M
1,152,000
2,000,000
2,062,500
2,500,000
3,125,000
3,750,000
TCR = 16
115,200
460,800
921,600
32
OXCF950 DATA SHEET V1.1
10.00M
2.50M
4.00M
5.00M
8.00M
40
Max. Baud rate
with CPR = 1,
3.125M
10.00M
12.50M
10,000,000
12,500,000
15,000,000
5.00M
6.25M
1,843,200
3,686,400
4,608,000
8,000,000
8,250,000
TCR = 4
460,800
50
10.00M
12.00M
15.00M
3.75M
4.00M
5.00M
6.00M
7.50M
60
Page 39