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MSM66577 Family User's Manual
Chapter 5 Port Functions
5.14 Port 10 (P10)
Port 10 is a 3-bit I/O port. Each individual bit can be specified as input or output by the port
10 mode register (P10IO). When output is specified (corresponding bits of P10IO = "1"),
the value of the corresponding bits in the port 10 data register (P10) will be output from their
appropriate pins.
In addition to its port function, P10 is assigned secondary functions (such as SIO4 transmit-
receive clock I/O). If a secondary function output is to be used, set the corresponding bits
of the port 10 mode register (P10IO) and the port 10 secondary function control register
(P10SF) to "1". If a secondary function input is to be used, reset corresponding bits of the
port 10 mode register (P10IO) to "0" to configure the input mode (same input as the primary
function input).
If the port is set as an input (corresponding bits of P10IO = "0") and the port 10 secondary
function control register (P10SF) is set to "1", the pin inputs corresponding to those bits will
be pulled-up.
If bit 5 of port 10 is set as secondary function outputs (P10IOn = 1, P10SFn = 1), the output
will be fixed at "0", regardless of the value of the port 10 data register.
Figure 5-17 shows the configuration of the port 10 data register (P10), port 10 mode register
(P10IO) and the port 10 secondary function control register (P10SF).
Figure 5-17 P10, P10IO, P10SF Configuration
7
—
6
5
4
3
2
1
0
P10IO3
P10IO5
—
7
—
6
5
4
3
2
1
0
SIOK4
P10SF3
—
——
7
—
6
5
4
3
2
1
0
P10_3
P10_5
—
000
0
00
0
00
0
P10SF3
—
P10IO4
SIOO4
P10SF3
P10_4
Not pulled-up
P10_3 output
Pulled-up
Secondary function
SIO4 transmit-
receive clock output
Not pulled-up
P10_4 output
Pulled-up
Secondary function
SIO4 transmit
data output
Not pulled-up
P10_5 input
SIO4 receive
cata input
Primary function
P10_5 output
Pulled-up
Secondary function
0 output*
0
1
0
1
0
1
0 (Input setting)
1 (Output setting)
P10IO
At reset
P10SF
At reset
P10
At reset
Address:
R/W access:
00CA [H]
R/W
P10_4 input
Primary function
Address:
R/W access:
00C2 [H]
R/W
Address:
R/W access:
00BA [H]
R/W
P10_3 input
SIO4 transmit-
receive clock input
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."