Samsung 8-Bit CMOS Microcontroller SIO PRE-SCALER Register Siops, SIO Prescaler Register Siops

S3C9228/P9228 SERIAL I/O INTERFACE

SIO PRE-SCALER REGISTER (SIOPS)

The prescaler register for serial I/O interface module, SIOPS, are located at E3H in page 0.

The value stored in the SIO pre-scale register, SIOPS, lets you determine the SIO clock rate (baud rate) as follows:

Baud rate = Input clock (fxx/4)/(Prescaler value + 1), or SCK input clock.

SIO Pre-scaler Register (SIOPS)

E3H, Page 0, R/W

MSB

.7

.6

.5

.4

.3

.2

.1

.0

LSB

Baud rate = (fXX/4)/(SIOPS + 1)

Figure 15-2. SIO Prescaler Register (SIOPS)

SIO BLOCK DIAGRAM

				3-Bit Counter			SIO INT
						INTPND2.2
					Clear
				CLK
						Pending
				SIOCON.3			SIOCON.1
							(Interrupt Enable)
			SIOCON.7
				SIOCON.4		SIOCON.2
				(Edge Select)		(Shift Enable)	SIOCON.5
SCK			M
							(Mode Select)
	SIOPS (E3H, page 0)		U	CLK	8-Bit SIO Shift Buffer
							SO
fxx/2	8-bit P.S.	1/2		(SIODATA, E2H, page 0)
			X
							SIOCON.6
							(LSB/MSB First
					8		Mode Select)
SI
					Data Bus

Figure 15-3. SIO Functional Block Diagram

15-3