Samsung C8278X Computer Hardware User Manual


 
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X I/O PORTS
9-19
PORT 6
Port 6 is a 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 F6H in set 1, bank 0. P6.0-P6.3 can serve as inputs (with or without pull-
up), as push-pull output or you can be configured the following functions.
Low-nibble pins (P6.0-P6.3): COM0COM3
Port 6 Control Register (P6CON)
Port 6 has an 8-bit control register: P6CON for P6.0-P6.3. A reset clears the P6CON register to "00H", configuring
all pins to input mode. You use control register setting to select input (with or without pull-up) or push-pull output
mode and enable the alternative functions.
When programming this port, please remember that any alternative peripheral I/O function you configure using the
port 6 control register must also be enabled in the associated peripheral module.
Port 6 Control Register (P6CON)
EDH, Set 1, Bank 1, R/W
.7 .6 .5 .4 .3 .2 .1 .0MSB LSB
P6.1/COM1 P6.0/COM0
P6CON bit-pair pin configuration settings:
00
01
10
11
Push-pull output mode
Alternative function (COM3-COM0)
Input with pull-up resistor
Input mode
P6.2/COM2P6.3/COM3
Figure 9-23. Port 6 Control Register (P6CON)