What do you mean open collector?

Deal with input ports output, helped article


I understand how to program a specific mode, but the question is what is each mode?

  • 00 – analog input.
    01 – the entrance is in the third state. (Set after reset).
    10 – input with pull-up resistor
    11 – reserved for future applications.

Analog input is the input which will be activated with different naprugi, for example for digitization in ADC?
The entrance is in the third state is high impedance state - ie the exit with wild resistance?
Input with pull-up resistor - this is the entrance which will be a logical level, right? but what is 1 or 0?
Reserved for future applications - then I do not really understand, but apparently if it is not worth it at all to use, and yet why?

go on...

  • 00 – digital output
    01 – digital output open drain
    10 – digital output connected to specialized units
    11 – digital output connected to specialized units with open drain

Digital output - with legs will be broadcast by a collection of zeros and ones corresponding to some letter?
Digital output open drain - what does it mean?
Digital output that is connected to the specialized units - what is this block? or as in the case reserved for future applications?
Digital output that is connected to specialized units with open drain - all fantasy was over.

Please correct my answers. In order to get data from the thermistor which mode is appropriate? what for the flashing led? Thank you!
July 9th 19 at 11:23
1 answer
July 9th 19 at 11:25
- open collector (drain)
- high-impedance state
- read about the appointment of the pull-up resistors and do highly recommend this website for learning the basics.

To connect the thermistor you need to build a voltage divider for the thermistor and the resistor of known value and measure issued by this voltage divider using the input operating in analog mode. The data will go to the inbuilt ADC of the controller.
To use the led it is possible to take the open drain output and through a current limiting resistor to connect the led. Anode to the positive pole of the power source, the cathode through a resistor to the microcontroller output. Install the output 0 led turn on, 1 - off.

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