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Сообщение от Segel06
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Здравствуйте.
На реальном устройстве всегда показывает на входе 5В,
даже если все ноги порта А "висят" в воздухе.
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Надо отключить резистор привязки к 5 Вольтам.
When using the ADC, remember the following:
• The Port Pin for the ADC channel in use must be configured to be an input with pull-up
disabled to avoid signal contention.
Configuring the Pin Each port pin consists of three register bits: DDxn, PORTxn, and PINxn. As shown in “Register
Description for I/O Ports” on page 64, the DDxn bits are accessed at the DDRx I/O address, the
PORTxn bits at the PORTx I/O address, and the PINxn bits at the PINx I/O address.
The DDxn bit in the DDRx Register selects the direction of this pin. If DDxn is written logic one,
Pxn is configured as an output pin. If DDxn is written logic zero, Pxn is configured as an input
pin.
If PORTxn is written logic one when the pin is configured as an input pin, the pull-up resistor is
activated. To switch the pull-up resistor off, PORTxn has to be written logic zero or the pin has to
be configured as an output pin. The port pins are tri-stated when a reset condition becomes
active, even if no clocks are running.
If PORTxn is written logic one when the pin is configured as an output pin, the port pin is driven
high (one). If PORTxn is written logic zero when the pin is configured as an output pin, the port
pin is driven low (zero).
When switching between tri-state ({DDxn, PORTxn} = 0b00) and output high ({DDxn, PORTxn}
= 0b11), an intermediate state with either pull-up enabled ({DDxn, PORTxn} = 0b01) or output
low ({DDxn, PORTxn} = 0b10) must occur. Normally, the pull-up enabled state is fully accept-
able, as a high-impedant environment will not notice the difference between a strong high driver
and a pull-up. If this is not the case, the PUD bit in the SFIOR Register can be set to disable all
pull-ups in all ports.
. На Атмеге8 для ЖКИ нет коррекции для заполярных широт и возможно появление времени выключения более 24 часов (например 24 часа 16 минут), что соответственно приводит к неправильному управлению светом. В этом случае необходимо выставить коррекцию "0").
