ST7DALIF2 STMicroelectronics, ST7DALIF2 Datasheet - Page 63

• Manufacturer Part Number: ST7DALIF2
• Description: 8-BIT MCU WITH SINGLE VOLTAGE FLASH MEMORY, DATA EEPROM, ADC, TIMERS, SPI
• Manufacturer: STMicroelectronics

Specifications of ST7DALIF2

• 8 Kbytes Single Voltage Flash Program Memory With Read-out Protection, In-circuit Programming And In-application Programming (icp And Iap). 10k Write/erase Cycles Guaranteed, Data Retention: 20 years at 55°C.
• 256 Bytes Data Eeprom With Read-out Protection. 300k Write/erase Cycles Guaranteed, Data Retention: 20 years at 55°C.
• Clock Sources: Internal 1% RC oscillator, crystal/ceramic resonator or external clock
• Five Power Saving Modes: Halt, Active-Halt, Wait and Slow, Auto Wake Up From Halt

ST7DALIF2
12.2.3
Caution:
Alternate functions
Many ST7s I/Os have one or more alternate functions. These may include output signals
from, or input signals to, on-chip peripherals. The
describes which peripheral signals can be input/output to which ports.
A signal coming from an on-chip peripheral can be output on an I/O. To do this, enable the
on-chip peripheral as an output (enable bit in the peripheral’s control register). The
peripheral configures the I/O as an output and takes priority over standard I/O programming.
The I/O’s state is readable by addressing the corresponding I/O data register.
Configuring an I/O as floating enables alternate function input. It is not recommended to
configure an I/O as pull-up as this will increase current consumption. Before using an I/O as
an alternate input, configure it without interrupt. Otherwise spurious interrupts can occur.
Configure an I/O as input floating for an on-chip peripheral signal which can be input and
output.
I/Os which can be configured as both an analog and digital alternate function need special
attention. The user must control the peripherals so that the signals do not arrive at the same
time on the same pin. If an external clock is used, only the clock alternate function should be
employed on that I/O pin and not the other alternate function.
Figure 30. I/O port general block diagram
REGISTER
ACCESS
REQUEST (ei
EXTERNAL
INTERRUPT
DDR SEL
OR SEL
DR SEL
DDR
OR
DR
x
)
SENSITIVITY
SELECTION
ALTERNATE
OUTPUT
From on-chip periphera
ALTERNATE
ENABLE
BIT
If implemented
1
0
Combinational
Logic
l
1
0
FROM
OTHER
BITS
Note: Refer to the Port Configuration
table for device specific information.
Table 2: Device pin description on page 14
N-BUFFER
PULL-UP
CONDITION
SCHMITT
TRIGGER
CMOS
V
DD
P-BUFFER
(see table below)
To on-chip peripheral
V
DD
DIODES
(see table below)
PULL-UP
(see table below)
ALTERNATE
ANALOG
I/O ports
INPUT
INPUT
PAD
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