ST7262
I/O PORTS (Cont’d)
Analog Alternate Functions
When the pin is used as an ADC input, the I/O
must be configured as input. The analog multiplex-
er (controlled by the ADC registers) switches the
analog voltage present on the selected pin to the
common analog rail which is connected to the
ADC input.
It is recommended not to change the voltage level
or loading on any port pin while conversion is in
progress. Furthermore it is recommended not to
have clocking pins located close to a selected an-
alog pin.
Warning: The analog input voltage level must be
within the limits stated in the Absolute Maximum
Ratings.
9.2.4 I/O Port Implementation
The hardware implementation on each I/O port de-
pends on the settings in the DDR register and spe-
cific features of the I/O port such as ADC Input or
true open drain.
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