All Questions
Tagged with pull-up arduino-uno
11 questions
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How to test custom cables?
I'm trying to make a cable checker to help me make custom cables for my computer. I'm thinking I plug the cable ends into sockets on the device, then the Arduino checks between different pins to make ...
- 11
1
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0
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339
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Arduino pull-up resistor not working
I made a circuit where when I press a button, a LED lights up using a pull-down resistor. But when I tried the same with a pull-up resistor instead, the LED remains off (whereas I expected it to be on ...
- 11
2
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1
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1k
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Configure input pullup through registers
I can set pin mode to input or output through the DDRx registers. How can I enable the internal pullup resister through a register?
- 127
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1
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10k
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How many UNO pins have internal pull up resistors?
I am referring to all digital I/O pins 0 to 13 and A0 to A5.
1
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3
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11k
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Do I need a pull-up/down resistor for button LED circuit?
When reading up on how to make a circuit that turns an LED on when a button is held down, I keep finding people saying a pull up or down resistor must be involved, to avoid the flickering state of the ...
- 113
2
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2
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6k
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Minimum value I2C-pull up resistor for arduino
I'm trying to determine the minimum value of pull resistor for Arduino Uno
The datasheets says for arduino; VOL = 0,4 for IOL = 20 mA. (VDD = 5V)
For formula for calculation of minimal pull-up is: ...
- 21
1
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3
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5k
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digitalRead not reading input pin of ESP8266-01
I am trying to use a on-off switch with the ESP8266 to change whether GPI02 is HIGH or LOW. I am using GPIO3 as input. My circuit looks like this:
The red area to the right is a relay, I wasn't sure ...
- 173
0
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1
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598
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How do I pull up D1-D6 using 10k ohm resistors?
I'm using push buttons to control CR servos (button1=turn CW; button2=turn CCW). How do I pull up D1-D6 and what does that do exactly? I can't find a tutorial that explains it well enough how to use ...
- 103
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2
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192
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Digital Pin State - Some 1, Some 0
I'm running a sketch that looks for inputs to digital pins 3, 4, 5, 6, and 7. The gist of the sketch is that it's a digitalRead() from 3-7 with a Serial.println() to the monitor. The odd thing is ...
- 653
0
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1
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2k
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Second I2C address not accepted
I have set up 2 DHT22 sensors and 2 BMP280 sensors with an Arduino Uno SMD R3 board. The DHTs are working fine and are outputting correct temperature and humidity values to the Serial monitor. The ...
- 85
2
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15k
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Disabling i2c internal pull up resistors
How do you do this? I've been digging around and I can see that I should do this and supply my own external pull up resistors but I don't know exactly how to disable them. The pages I've been reading ...
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