S3CK215 Datasheet, PDF (187/245 Pages) Samsung semiconductor – CalmRISC 8-Bit CMOS Microcontroller

SERIAL I/O INTERFACE
SIO CONTROL REGISTER (SIOCON)
S3CK215/FK215
Serial I/O Module Control Register (SIOCON)
58H, R/W, Reset: 00H
MSB .7 .6 .5 .4 .3 .2 .1 .0 LSB
SIO shift clock select bit:
0 = Internal clock (P.S clock)
1 = External clock (SCK)
Data direction control bit:
0 = MSB-first
1 = LSB-first
SIO mode selction bit:
0 = Rececive-only mode
1 = Transmit/receive mode
Not used
SIO shift operation enable bit:
0 = Disable shifter and clock
1 = Enable shfter and clock
SIO counter clear and shift start bit:
0 = No action
1 = Clear 3-bit counter and start shifting
Shift clock edge selction bit:
0 = Tx at falling edge, Rx at rising edge
1 = Tx at rising edge, Tx at falling edge
Figure 17-1. Serial I/O Module Control Registers (SIOCON)
SIO PRE-SCALER REGISTER (SIOPS)
The value stored in the SIO pre-scaler registers, SIOPS, lets you determine the SIO clock rate (baud rate) as
follows:
Baud rate = Input clock( fxx/4)/(Pre-scaler value + 1), or, SCK input clock
where fxx is a selected clock.
MSB .7
SIO Pre-scaler Register (SIOPS)
59H,R/W, Reset: 00H
.6 .5 .4 .3 .2 .1
.0 LSB
Baud rate = (fxx/4)/(SIOPS + 1)
Figure 17-2. SIO Pre-scaler Register (SIOPS)
17-2