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ST7LITEUS2, ST7LITEUS5
I/O ports
63/136
Caution:
The alternate function must not be activated as long as the pin is configured as input with
interrupt, in order to avoid generating spurious interrupts.
Analog alternate function
When the pin is used as an ADC input, the I/O must be configured as floating input. The
analog multiplexer (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 analog pin.
Warning:
The analog input voltage level must be within the limits
stated in the absolute maximum ratings.
9.3
Unused I/O pins
Unused I/O pins must be connected to fixed voltage levels. Refer to
.
9.4
Low power modes
9.5 Interrupts
The external interrupt event generates an interrupt if the corresponding configuration is
selected with DDR and OR registers and the interrupt mask in the CC register is not active
(RIM instruction).
Table 20.
Effect of low power modes on I/O ports
Mode
Description
Wait
No effect on I/O ports. External interrupts cause the device to exit from Wait
mode.
Halt
No effect on I/O ports. External interrupts cause the device to exit from Halt
mode.
Table 21.
Description of interrupt events
Interrupt event
Event flag
Enable
control bit
Exit from
Wait
Exit from
Halt
External interrupt on selected
external event
-
DDRx
ORx
Yes
Yes
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