Samsung S3C8275X - Manual (Page 252)

S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X I/O PORTS
9-17
PORT 5
Port 5 is an 8-bit I/O port with individually configurable pins. Port 5 pins are accessed directly by writing or reading
the port 5 data register, P5 at location F5H in set 1, bank 0. P5.0-P5.7 can serve as inputs (with or without pull-
up), as push-pull output or you can be configured the following functions.
• Low-nibble pins (P5.0-P5.3): SEG7−SEG4
• High-nibble pins (P5.4-P5.7): SEG3−SEG0
Port 5 Control Registers (P5CONH, P5CONL)
Port 5 has two 8-bit control registers: P5CONH for P5.4-P5.7 and P5CONL for P5.0-P5.3. A reset clears the
P5CONH and P5CONL registers to "00H", configuring all pins to input mode. You use control registers 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 5 control registers must also be enabled in the associated peripheral module.
Port 5 Control Register, High Byte (P5CONH)
EBH, Set 1, Bank 1, R/W
.7 .6 .5 .4 .3 .2 .1 .0 MSB LSB
P5.5/SEG2 P5.4/SEG3
P5CONH bit-pair pin configuration settings:
00
01
10
11
Push-pull output mode
Alternative function (SEG0-SEG3)
Input with pull-up resistor
Input mode
P5.6/SEG1 P5.7/SEG0
Figure 9-21. Port 5 High-Byte Control Register (P5CONH)