ST10F269Z2QX Datasheet, PDF (66/161 Pages) STMicroelectronics – 16-BIT MCU WITH MAC UNIT, 256K BYTE FLASH MEMORY AND 12K BYTE RAM

ST10F269Z2Qx
12.5 - Port 2
If this 16-bit port is used for general purpose I/O, the direction of each line can be configured via the
corresponding direction register DP2. Each port line can be switched into push/pull or open drain mode
via the open drain control register ODP2.
P2 (FFC0h / E0h)
SFR
Reset Value: 0000h
15 14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
P2.15 P2.14 P2.13 P2.12 P2.11 P2.10 P2.9 P2.8 P2.7 P2.6 P2.5 P2.4 P2.3 P2.2 P2.1 P2.0
RW RW RW RW RW RW RW RW RW RW RW RW RW RW RW RW
P2.y
Port Data Register P2 Bit y
DP2 (FFC2h / E1h)
SFR
Reset Value: 0000h
15 14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
DP2 DP2 DP2 DP2 DP2 DP2 DP2 DP2 DP2 DP2 DP2 DP2 DP2 DP2 DP2 DP2
.15 .14 .13 .12 .11 .10 .9 .8 .7 .6 .5 .4 .3 .2 .1 .0
RW RW RW RW RW RW RW RW RW RW RW RW RW RW RW RW
DP2.y
Port Direction Register DP2 Bit y
DP2.y = 0: Port line P2.y is an input (high-impedance)
DP2.y = 1: Port line P2.y is an output
ODP2 (F1C2h / E1h)
ESFR
Reset Value: 0000h
15 14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
ODP2 ODP2 ODP2 ODP2 ODP2 ODP2 ODP2 ODP2 ODP2 ODP2 ODP2 ODP2 ODP2 ODP2 ODP2 ODP2
.15 .14 .13 .12 .11 .10 .9 .8 .7 .6 .5 .4 .3 .2 .1 .0
RW RW RW RW RW RW RW RW RW RW RW RW RW RW RW RW
ODP2.y
Port 2 Open Drain Control Register Bit y
ODP2.y = 0: Port line P2.y output driver in push/pull mode
ODP2.y = 1: Port line P2.y output driver in open drain mode
12.5.1 - Alternate Functions of Port 2
All Port 2 lines (P2.15...P2.0) serve as capture
inputs or compare outputs (CC15IO...CC0IO) for
the CAPCOM1 unit.
When a Port 2 line is used as a capture input, the
state of the input latch, which represents the state
of the port pin, is directed to the CAPCOM unit via
the line “Alternate Pin Data Input”. If an external
capture trigger signal is used, the direction of the
respective pin must be set to input.
If the direction is set to output, the state of the port
output latch will be read since the pin represents
the state of the output latch.
This can be used to trigger a capture event
through software by setting or clearing the port
latch. Note that in the output configuration, no
external device may drive the pin, otherwise
conflicts would occur.
When a Port 2 line is used as a compare output
(compare modes 1 and 3), the compare event (or
the timer overflow in compare mode 3) directly
effects the port output latch. In compare mode 1,
when a valid compare match occurs, the state of
the port output latch is read by the CAPCOM
control hardware via the line “Alternate Latch Data
Input”, inverted, and written back to the latch via
the line “Alternate Data Output”.
The port output latch is clocked by the signal
“Compare Trigger” which is generated by the
CAPCOM unit. In compare mode 3, when a match
occurs, the value '1' is written to the port output
latch via the line “Alternate Data Output”. When
an overflow of the corresponding timer occurs, a
'0' is written to the port output latch. In both cases,
the output latch is clocked by the signal “Compare
Trigger”.
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