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MSM66577 Family User's Manual
Chapter 5 Port Functions
5
5.17 Port 14 (P14)
Port 14 is a 5-bit I/O port. Each individual bit can be specified as input or output by the port
14 mode register (P14IO). When output is specified (corresponding bits of P14IO = "1"),
the value of the corresponding bits in the port 14 data register (P14) will be output from their
appropriate pins.
In addition to its port function, P14 is assigned secondary functions (such as SIO5 receive
data input). If a secondary function output is to be used, set the corresponding bits of the
port 14 mode register (P14IO) and the port 14 secondary function control register (P14SF)
to "1". If a secondary function input is to be used, reset corresponding bits of the port 14
mode register (P14IO) to "0" to configure the input mode (same input as the primary function
input).
If the port is configured as an input (corresponding bits of P14IO = "0") and the port 14
secondary function control register (P14SF) is set to "1", inputs will be pulled-up at the pins
corresponding to those bits.
If bit 2 of port 14 is configured as a secondary function output (P14IO0 = 1, P14SF0 = 1),
the output will be fixed at "0", regardless of the value of the port 14 data register.
Figure 5-20 shows the configuration of the port 14 data register (P14), port 14 mode register
(P14IO) and the port 14 secondary function control register (P14SF).
7
6
5
4
3
2
1
0
—
P14IO2 P14IO1
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
P14_7
—
P14_2
P14_1
000
0
00
0
00
000
0
—
P14SF2
SIOO5
P14SF1
—
AO0
P14SF6
AO1
P14SF7
P14IO6
—
P14_6
—
P14IO7
P14IO0
P14_0
SIOCK5
P14SF0
0
Not pulled-up
P14_0 input
SIO5 transmit-
receive clock input
Primary function
P14_0 output
1
Pulled-up
Secondary function
SIO5 transmit-
receive clock output
Not pulled-up
P14_1 input
P14_2 input
SIO5 receive
data input
P14_6 input
Primary function
P14_1 output
Pulled-up
Secondary function SIO5 transmit
data output
Not pulled-up
Primary function
P14_2 output
Pulled-up
Secondary function
0 output*
Not pulled-up
P14_6 output
Pulled-up
Secondary function DA0 data output
0
1
0
1
0
1
0 (Input setting)
1 (Output setting)
P14IO
At reset
P14SF
At reset
P14
At reset
Address:
R/W access:
00C6 [H]
R/W
Address:
R/W access:
00C4 [H]
R/W
Address:
R/W access:
00BF [H]
R/W
Primary function
0 output*: "0" is output, regardless of the value of the port data register
"—" indicates a bit that does not exist. If read, the value will be "0."
P14_7 input
Not pulled-up
P14_7 output
Pulled-up
Secondary function DA1 data output
0
1
Primary function
Figure 5-20 P14, P14IO, P14SF Configuration