ST10F167 Datasheet, PDF (31/69 Pages) STMicroelectronics – 16-BIT MCU WITH 128K BYTE FLASH MEMORY

ST10F167
16 PARALLEL PORTS
The ST10F167 provides up to 77 I/O lines which
are organized into eight input/output ports and one
input port. All port lines are bit-addressable, and all
input/output lines are individually (bit-wise) pro-
grammable as inputs or outputs via direction regis-
ters. The I/O ports are true bidirectional ports
which are switched to high impedance state when
configured as inputs. The output drivers of three I/
O ports can be configured (pin by pin) for push/pull
operation or open-drain operation via control reg-
isters. During the internal reset, all port pins are
configured as inputs.
The input threshold of Port 2, Port 3, Port 7 and
Port 8 is selectable (TTL or CMOS like). The spe-
cial CMOS like input threshold reduces noise sen-
sitivity due to the input hysteresis. The input
threshold may be selected individually for each
byte of the respective ports.
All port lines have programmable alternate input or
output functions associated with them. PORT0
and PORT1 may be used as address and data
lines when accessing external memory, while Port
4 outputs the additional segment address bits A23/
19/17...A16 in systems where segmentation is en-
abled to access more than 64KBytes of memo-
ry.Port 2, Port 8 and Port 7 are associated with the
capture inputs or compare outputs of the CAP-
COM units and/or with the outputs of the PWM
module. Port 6 provides optional bus arbitration
signals (BREQ, HLDA, HOLD) and chip select sig-
nals. Port 3 includes alternate functions of timers,
serial interfaces, the optional bus control signal
BHE and the system clock output (CLKOUT).
Port 5 is used for the analog input channels to the
A/D converter or timer control signals.
All port lines that are not used for these alternate
functions may be used as general purpose IO
lines.
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