I/O PORTS
S3C4510B
I/O PORT SPECIAL REGISTERS
Three registers control the I/O port configuration: IOPMOD, IOPCON, and IOPDATA. These registers are
described in detail below.
I/O PORT MODE REGISTER (IOPMOD)
The I/O port mode register, IOPMOD, is used to configure the port pins, P17–P0.
NOTE
If the port is used for a special function such as an external interrupt request, an external DMA request,
or acknowledge signal and timer outputs, its mode is determined by the IOPCON register, not by
IOPMOD.
Table 12-1. IOPMOD Register
Register
IOPMOD
Offset Address
R/W
Description
I/O port mode register
Reset Value
0x5000
R/W
0x00000000
31
18 17 16 15 14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
[0] I/O port mode bit for port 0
0 = Input
1 = Output
[1] I/O port mode bit for port 1
0 = Input
1 = Output
[2] I/O port mode bit for port 2
0 = Input
1 = Output
[17] I/O port mode bit for port 17
0 = Input
1 = Output
Figure 12-2. I/O Port Mode Register (IOPMOD)
12-2
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