Reference Manual

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Where UBRDIVn is integer part of DIV_VAL - and UDIVSLOTn the floating point part of
DIV_VAL.
For example, if the baud rate is 115200 bps and SRCCLK is 66 MHz, UBRDIVn and
UDIVSLOTn are:
DIV_VAL = (66000000 / (115200 x 16)) -1
= 35.8 -1
= 34.8
* UBRDIVn = 34
(num of 1's in UDIVSLOTn)/16 = 0.8
(num of 1's in UDIVSLOTn) = 12.8=>13
The table below shows the recommended value table of UDIVSLOTn register.
As a result, DIV_VAL = 34.8125 = 34+13x(1/16)
The baud rate is finally:
66000000/(34.8125+1)/16 = 115167.2 baud
SPI interface The S3C2443 provides two SPI-interfaces, each of which have two 8-bit shift registers
for transmission and receiving, respectively. During an SPI transfer, data is
simultaneously transmitted (shifted out serially) and received (shifted in serially).
Four I/O pin signals are associated with SPI transfers: SCK (SPICLK0,1), MISO
(SPIMISO0,1) data line, MOSI (SPIMOSI0,1) data line, and the active low /SS (nSS0,1)
pin.
Both 4-pin SPI interfaces are provided at the system connector (Clock, Chip-Select,
Data-In and Data-Out). SPI0 interface is located at the general pins of the system
connector, while SPI1 interface shares its pins with interrupt functions at the specific
pins of the system connector.
Num of 1’s UDIVSLOTn Num of 1’s UDIVSLOTn
0 0x0000(0000_0000_0000_0000b) 8 0x5555(0101_0101_0101_0101b)
1 0x0080(0000_0000_0000_1000b) 9 0xD555(1101_0101_0101_0101b)
2 0x0808(0000_1000_0000_1000b) 10 0xD5D5(1101_0101_1101_0101b)
3 0x0888(0000_1000_1000_1000b) 11 0xDDD5(1101_1101_1101_0101b)
4 0x2222(0010_0010_0010_0010b) 12 0xDDDD(1101_1101_1101_1101b)
5 0x4924(0100_1001_0010_0100b) 13 0xDFDD(1101_1111_1101_1101b)
6 0x4A52(0100_1010_0101_0010b) 14 0xDFDF(1101_1111_1101_1111b)
7 0x54AA(0101_0100_1010_1010b) 15 0xFFDF(1111_1111_1100_1111b)