SERIAL I/O INTERFACE S3C9228/P9228
15-2
SIO CONTROL REGISTERS (SIOCON)
The control register for serial I/O interface module, SIOCON, is located at E1H in page 0. It has the control
setting 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 Register (SIOCON)
E1H, Page 0, R/W
.7 .6 .5 .4 .3 .2 .1 .0MSB LSB
SIO interrupt enable bit:
0 = Disable SIO interrupt
1 = Enable SIO interrupt
Not used
SIO shift operation enable bit:
0 = Disable shifter and clock counter
1 = Enable shifter and clock counter
Shift clock edge selection bit:
0 = tX at falling edeges, rx at rising edges.
1 = tX 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)
Figure 15-1. Serial I/O Module Control Register (SIOCON)