Samsung S3C84I8 User Manual page 281

S3C84I8/F84I8/84I9/F84I9
SIO PRESCALER REGISTER (SIOPS)
The control register for serial I/O interface module, SIOPS is located in Set 1, Bank 1 at F0H.
The value stored in the SIO prescaler registers, SIOPS, lets you determine the SIO clock rate (baud rate)
as follows:
Baud rate = Input clock(Xin/4) / (SIOP+ 1), or external SCK input clock
SCK
SIOPS(F4H)
8-Bit
XIN/2
Prescaler
Prescaler Value =
1/(SIOPS + 1)
SI
SIO Pre-Scaler Registers (SIOPS)
F0H, SET1, Bank 1, R/W
MSB .7 .6 .5
Baud Rate = (X
Figure 14-2. SIO Pre-Scaler Register (SIOPS)
CLK
SIOCON.7
(Shift Clock
Source Select)
MUX
1/2
Toggle
Figure 14-3. SIO Functional Block Diagram
.4 .3 .2 .1
/4)/(SIOPS+1)
IN
3-Bit Counter Clear
SIOCON.3
SIOCON.4 SIOCON.2
(Edge Select) (Shift Enable)
CLK
8-Bit SIO Shift Buffer
(SIODATA)
8
Data Bus
SERIAL I/O INTERFACE
.0 LSB
SIOCON.0
Pending
SIOCON.1
(Interrupt Enable)
SIOCON.5
(Mode Select)
SIOCON.6
(LSB/MSB
First
Mode Select)
SIO INT
SO
14-3