Samsung 8-Bit CMOS Microcontroller Microcassette Recorder User Manual


 
I/O PORTS S3C9228/P9228
9-16
PORT 6
Port 6 is an 4-bit I/O port with individually configurable pins. Port 6 pins are accessed directly by writing or
reading the port 6 data register, P6 at location EAH in page 0. P6.0-P6.3 can serve as inputs or as push-pull,
open-drain outputs. You can configure the following alternative functions with LCD port control register, LPOT:
Low-nibble pins (P6.0-P6.3): COM0-COM3
Port 6 Control Register (P6CON)
Port 6 has a 8-bit control register: P6CONH for P6.0-P6.3. A reset clears the P6CON registers to "00H",
configuring all pins to input mode. You use control registers setting to select input or output mode.
Port 6 Control Register, Low Byte (P6CON)
FDH, Page 0, R/W
.7 .6 .5 .4 .3 .2 .1 .0MSB LSB
P6.1/COM2 P6.0/COM3
P6CON bit-pair pin configuration settings:
00
01
10
11
N-channel open-drain output mode
Input mode with pull-up
Push-pull output mode
Input mode
P6.2/COM1P6.3/COM0
Figure 9-23. Port 6 Control Register (P6CON)