Samsung S3C8245 User Manual

The control register for serial I/O interface module, SIOCON, is located at F0H  in set 1, bank 0. It has the control
settings for SIO module.

— Clock source selection (internal or external) for shift clock

— Interrupt enable

— Edge selection for shift operation

— Clear 3-bit counter and start shift operation

— Shift operation (transmit) enable

— Mode selection (transmit/receive or receive-only)

— Data direction selection (MSB first or LSB first)

A reset clears the SIOCON value to "00H". This configures the corresponding module with an internal clock source
at the SCK, selects receive-only operating mode, and clears the 3-bit counter. The data shift operation and the
interrupt are disabled. The selected data direction is MSB-first.

Serial I/O Module Control Registers (SIOCON)

F0H, Set 1, Bank 0, R/W

.7

.6

.5

.4

.3

.2

.1

.0

MSB

LSB

SIO interrupt enable bit
0 = Disable SIO interrupt
1 = Enable SIO interrupt

SIO interrupt pending bit
0 = No interrupt pending
0 = Clear pending condition
      (when write)
1 = Interrupt is pending

SIO shift operation enable bit
0 = Disable shifter and clock counter
1 = Enable shifter and clock counter

Shift clock edge selection bit
0 = T

X

 at falling edeges, Rx at rising edges

1 = T

X

 at rising edeges, Rx at falling edges

Data direction control bit
0 = MSB-first mode
1 = LSB-first mode

SIO mode selection bit
0 = Receive only mode
1 = Transmit/receive mode

SIO counter clear and shift start bit
0 = No action
1 = Clear 3-bit counter and start shifting

SIO shift clock selection bit
0 = Internal clock (P.S Clock)
1 = External clock (SCK)