ST ST10R272L, User Manual

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ST10R272L - PARALLEL PORTS
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Due to pin limitations register bit P3.14 is not connected to an output pin.
P3 (FFC4h / E2h) SFR Reset Value: 0000h
Note Register bit P3.14 is not connected to an I/O pin.
DP3 (FFC6h / E3h) SFR Reset Value: 0000h
ODP3 (F1C6h / E3h) ESFR Reset Value: 0000h
7.4.1 Alternate functions of Port 3
The pins of Port 3 serve for various functions which include external timer control lines, the
two serial interfaces and the control lines BHE and CLKOUT.
Bit Function
P3.y Port data register P3 bit y
Bit Function
DP3.y
Port direction register DP3 bit y
DP3.y = 0: Port line P3.y is an input (high-impedance)
DP3.y = 1: Port line P3.y is an output
Bit Function
ODP3.y
Port 3 Open Drain control register bit y
ODP3.y = 0: Port line P3.y output driver in push/pull mode
ODP3.y = 1: Port line P3.y output driver in open drain mode
5 4 3 2 1 0 11 10 9 8 7 6 15 14 13 12
rw rw rw rw rw rw rw rw rw rw rw rw rw - rw rw
P3.0 P3.1 P3.2 P3.3 P3.4 P3.5 P3.6 P3.7 P3.8 P3.9 P3.10 P3.11 P3.12 P3.13 - P3.15
5 4 3 2 1 0 11 10 9 8 7 6 15 14 13 12
rw rw rw rw rw rw rw rw rw rw rw rw rw - rw rw
DP3 DP3 DP3 DP3 DP3 DP3 DP3 DP3 DP3 DP3 DP3 DP3 DP3
-
DP3 DP3
5 4 3 2 1 0 11 10 9 8 7 6 15 14 13 12
rw rw rw rw rw rw rw rw rw rw rw rw - - rw -
ODP3
.13
ODP3
.11
ODP3
.10
ODP3
.9
ODP3
.8
ODP3
.7
ODP3
.6
ODP3
.5
ODP3
.4
ODP3
.3
ODP3
.2
ODP3
.1
ODP3
.0
- - -