st10f272z2 STMicroelectronics, st10f272z2 Datasheet - Page 19

• Manufacturer Part Number: st10f272z2
• Description: 16-bit Mcu With 256 Kbyte Flash Memory And 20 Kbyte Ram
• Manufacturer: STMicroelectronics

ST10F272Z2
Table 2.
P0L.0 -P0L.7,
P1L.0 - P1L.7
EA / V
Symbol
P0H.1 -
P1H.0 -
P0H.0
P0H.7
P1H.7
STBY
Pin description (continued)
100-107,
111-117
118-125
128-135
108,
132
133
134
135
Pin
99
Type
I/O
I/O
I
I
I
I
I
External access enable pin.
A low level applied to this pin during and after Reset forces the ST10F272Z2 to
start the program from the external memory space. A high level forces
ST10F272Z2 to start in the internal memory space. This pin is also used (when
Stand-by mode is entered, that is ST10F272Z2 under reset and main V
off) to bias the 32 kHz oscillator amplifier circuit and to provide a reference
voltage for the low-power embedded voltage regulator which generates the
internal 1.8V supply for the RTC module (when not disabled) and to retain data
inside the Stand-by portion of the XRAM (16Kbyte).
It can range from 4.5 to 5.5 V (6V for a reduced amount of time during the device
life, 4.0V when RTC and 32 kHz on-chip oscillator amplifier are turned off). In
running mode, this pin can be tied low during reset without affecting 32 kHz
oscillator, RTC and XRAM activities, since the presence of a stable V
guarantees the proper biasing of all those modules.
Two 8-bit bidirectional I/O ports P0L and P0H, bit-wise programmable for input or
output via direction bit. Programming an I/O pin as input forces the corresponding
output driver to high impedance state. The input threshold of Port 0 is selectable
(TTL or CMOS).
In case of an external bus configuration, PORT0 serves as the address (A) and
as the address / data (AD) bus in multiplexed bus modes and as the data (D) bus
in demultiplexed bus modes.
Demultiplexed bus modes
Multiplexed bus modes
Two 8-bit bidirectional I/O ports P1L and P1H, bit-wise programmable for input or
output via direction bit. Programming an I/O pin as input forces the corresponding
output driver to high impedance state. PORT1 is used as the 16-bit address bus
(A) in demultiplexed bus modes: if at least BUSCONx is configured such the
demultiplexed mode is selected, the pis of PORT1 are not available for general
purpose I/O function. The input threshold of Port 1 is selectable (TTL or CMOS).
The pins of P1L also serve as the additional (up to 8) analog input channels for
the A/D converter, where P1L.x equals ANy (Analog input channel y,
where y = x + 16). This additional function have higher priority on demultiplexed
bus function.
The following PORT1 pins have alternate functions:
P1H.4
P1H.5
P1H.6
P1H.7
Data path width
P0L.0 – P0L.7:
P0H.0 – P0H.7:
Data path width
P0L.0 – P0L.7:
P0H.0 – P0H.7:
CC24IO
CC25IO
CC26IO
CC27IO
8-bit
D0 – D7
I/O
8-bit
AD0 – AD7
A
8 – A15
CAPCOM2: CC24 capture input
CAPCOM2: CC25 capture input
CAPCOM2: CC26 capture input
CAPCOM2: CC27 capture input
Function
16-bi
D0 - D7
D8 - D15
16-bi
AD0 - AD7
A
D8 - AD15
DD
DD
Pin data
turned
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