Questions tagged [pins]

"Pins" are like gateways between the Arduino code running on the chip and the components attached to Arduino. It can refer either to the physical connectors on the board, or it can refer to the pins defined in the code.

Filter by
Sorted by
Tagged with
0
votes
0answers
28 views

What is the equivilent of PORTx for Teensy (4.0)?

I've seen people use code like PORTB |= 0x1 << 6 to set the sixth bit of PORTB in arduino. I understand that this is significantly faster than using digitalWrite. How can this be done using a ...
0
votes
0answers
20 views

How to specify pin in Servo library?

Here's what caused the original confusion. As one know, Arduino nano and UNO use analog pin as PWM pins, while Arduino Mega use digital pin output as the PWM pins, which this webpage ignored to ...
0
votes
1answer
40 views

How to connect HC-06 BT module without pins?

So, from one popular Chinese store I ordered a HC-06 module that I received... and due to some mistake from a store, I received a HC-06 without connecting pins. So usually HC-06 looks like this (with ...
0
votes
1answer
48 views

Multiple variant.cpp entries for same physical pin

Some variant.cpp files have more than one entry that points to the same physical pin. For example (from Arduino Zero's file): // 14..19 - Analog pins // -------------------- { PORTA, 2, PIO_ANALOG, ...
1
vote
1answer
15 views

Help, I want to turn relay constantly on until a difference is detected, but triggered only one instead

Help, I want to use arduino to control relay for electricity, i get data from a sensor and when a value is detected it should be constantly on until another detection triggered again, i can get the ...
0
votes
2answers
50 views

USING HX711 ( WITH LOADCELL) WITH PCF8574 IN NODEMCU

I have used hx711 and loadcell with nodemcu (esp8266) in its D1 and D2 pins ( here I have used Logic level shifter and a 5v supply to power hx711).It worked perfectly fine. Due to the lack of enough ...
0
votes
0answers
29 views

Unable to get input from Wemos D1 PIR sensor

I am using the script below to create a motion sensor using a Wemos D1 and a PIR sensor. I'm using the ESP8266 Community board manager (V2.6.3). THE PROBLEM When I use the Wemos D1 R1 board no ...
0
votes
0answers
38 views

Non-Linear readings on Analog Pin A0 vs. other Pins A1

I discovered a curios behavior of my Nano v3. The analog Pin A0 seems to measure data in a non-linear way while the other pins seem to work normal. Please have a look at the screenshot. This is the ...
0
votes
1answer
65 views

Trying to read different gas levels with MQ2 Gas Sensor

I found a link on how to connect MQ-2 Gas Sensor to Arduino Uno. http://electronicsprojectshub.com/how-to-connect-mq2-gas-sensor-to-arduino/ After I bought all the parts and tried it out, the sensor ...
0
votes
1answer
43 views

Use JYETech 2.4 Inch LCD Display Screen Module with Arduino?

I have this JYETech 2.4 Inch LCD Display Screen Module that I would like to use for a project I have in mind, however, I'm not sure how to wire it up with my Arudino Mega. Here is the datasheet for ...
-2
votes
1answer
39 views

Can you use a 128 pin LCD on an atMega?

I found a couple old calculators and their LCD's have about 130 pins. I was wondering if I can build an LCD driver to reduce the number of I/O pins, because I don't want to use like 14 I/O extenders; ...
-1
votes
1answer
44 views

4:1: error: expected initializer before 'void' [closed]

int button void setup() { pinMode(13, OUTPUT); pinMode(12, OUTPUT); button 4; pinMode(4=INPUT); } void loop() { if(digitalRead(4)== LOW); { digitalWrite (13, HIGH); delay (250); ...
0
votes
1answer
39 views

Understanding analog pins in pinMode

When passing the pin number in pinMode its possible to use A0 - A7, does it apply only to that methode? How can pinMode expect a number (is it int?) type in case of digital pin another (is it then ...
1
vote
3answers
275 views

Issue connecting heartbeat & temperature sensor on arduino uno but working individually

So the code is working individually for temperature sensor and for heartbeat sensor but when i combine it together it shows wrong values for the temperature sensor I'm using lm35 temperature sensor ...
0
votes
1answer
141 views

Do some arduino pins give signals when the controller starts?

For example, on the ESP32 board there are several contacts that can issue pulses when the controller starts, which is connected with the operation of the chip itself. It is not recommended to connect ...
-3
votes
1answer
41 views

Can I power Raspberry Pi 3 via 3V3 and GND pin? [closed]

Can I power my Pi 3 using the 3v3 pin (pin 1) and GND pin (pin 6)? Also, if I want to protect the board from power surges can I just put a fuse between my power supply and the 3v3 pin? Thanks in ...
0
votes
1answer
50 views

Pin Mappings from Arduino Metro M4 Express Board to SAMD51

After looking through the internet, I coudln't find any document (not in the datasheet, no nice graphics on google image searches) that showed the mapping between the Arduino breakout board and the ...
0
votes
0answers
126 views

Made a light controller for the holidays

I am a new the world of Arduino. I found on YouTube, how to build a light controller (https://www.youtube.com/watch?v=WvG9c84ApFA&t=39s). I follow every step but it doesn't work. Here are some ...
-1
votes
1answer
35 views

Connecting 2-pin JST PH connector to Arduino Mega

I’m want to connect 50 LDR to my Mega, I wondering if I use a 2-female pin JST PH connector to connect the LDR, how can I link 2-pin male JST PH connector board to the Mega and does this board exist?
0
votes
0answers
39 views

HC-SRO4 always returns zero no matter what I do?

Wondering if it's the sensor or the code? can anyone help? I've used the code here /* HC-SR04 Ultrasonic Sensor with LCD dispaly HC-SR04 Ultrasonic Sensor VCC to Arduino 5V GND to Arduino GND ...
0
votes
2answers
79 views

Can a pin be Neutral, not high or low?

I'm trying to figure out a way to controll a DFplayer mini mp3 player with ADkeys. Because I only have two or three files to play at a fixed volume I find it easier to just use the ADkeys. https://...
-1
votes
1answer
425 views

How come some Arduino Nano pins (D3, D4, A3, A4, A6, A7) cannot be set high?

I made a sketch to switch on all digital and analog pins, and found out several pins did not work as expected. Note: I manually put a jumper wire from each digital and analog pin (one at a time) to a ...
0
votes
1answer
40 views

Running out of GPIO & looking for suggestions

I'm working on a project using a NodeMCU and am quickly running out of GPIO pins. I'm trying to decide which way to go to complete it. Right now, I have the MCU connected to a MAX31856 PT100 ...
0
votes
0answers
97 views

Using a 122x32 LCD display with u8g2

I recovered a 122x32 graphic LCD display, its reference is NMTB-S000087FYHSAY-04. Here are some pics It was retrieved from a completely rusted object, but the screen seems to work. It is a 122x32 ...
1
vote
1answer
24 views

Can I disable the TX pin by setting its mode to INPUT while still receiving data on the RX pin of a UART?

I'm using the ATmega328PB in a personal project with MiniCore. My board streams data in on the RX pin from another microcontroller, but my board also has a DIP switch connected to the TX pin, that's ...
0
votes
0answers
32 views

Creating WebServer with 5000 port with AT command(ESP-01f)

I'm setting webserver with toggle led. I want to create global webserver. I`m mean hat use server with global ip. For it I must use port too. global ip/local ip:port. I want to create on 5000 port. I'...
0
votes
1answer
33 views

Arduino Due Digital Inputs without Response

On two of my Arduino Due, when connecting the pin 3.3V to any digital inputs (37,36,35,34), no serial message nor LED_BUILTIN is thrown as output, only the Test message. Digital Pins are set as ...
1
vote
1answer
144 views

Output 3.3V when setting pin to high

I would like to pass 3.3V and Ground to an component. How can I achieve such a thing? I for example would like to let a wire get 3.3V when I for example do digitalWrite(pin, HIGH). It is hard for me ...
0
votes
2answers
44 views

How to set cables to connect Cp2102 to Pro Mini?

How to connect the cables in order to program the pro mini with the CP2102 usb interface ? The TX RX and GND is easy, but I am not sure about the RST, DTR, DST, etc I attached the images of both. ...
2
votes
2answers
191 views

measure +3V and -3V through resistor divider and switch on/off by digital pins

I've seen that resistor dividers can be used to read negative voltages, but I'ld like if there is a way to accomplish this with less components and having a way to turn this off. I was thinking if ...
2
votes
1answer
36 views

Which sources of randomness are available? [duplicate]

I need a souce of randomness to generate a seed to pass to randomSeed. Where can I get this randomness from? Well, I hear I can read random noise from an unconnected pin. But I need to connect 9 ...
1
vote
1answer
830 views

Can I use the PWM pins as regular digital input/output pins?

In regards to the arduino which has pwm pins, can I use these pins as normal input/output digital pins or not? Thanks in advance.
0
votes
0answers
44 views

HC-05 Bluetooth module on breakout board with straight header pins

Has anyone found the HC-05 bluetooth module (on the breakout board) with straight header pins? I seem to only be able to find them with the 90 degree header pins. Removing those and soldering on ...
1
vote
3answers
171 views

Is there an alternative to soldering to connect boards?

I know that shields are usually soldered to headers so they can be attached to the board with the Arduino. I have a tremor, which makes soldering impossible. Are there ways of connecting PCBs without ...
-3
votes
1answer
34 views

Spi based pin expander for Arduino

I don't have enough pins on my Esp32 board. I would like to use a pin expander. All the ones I could find online only use i2c. Are there ones available that use SPI? I would like send pwm signals to ...
0
votes
1answer
26 views

What type of power supply is the Arduino Due’s 5v pin and what is its current?

I’m looking to use a Futaba Servo with my arduino Due and was told it requires a “high current 5 volt supply” and I don’t know much about current so excuse my arrogance. I know the arduino Due has a 5 ...
0
votes
2answers
45 views

Ways to add pins in an arduino

I'm making a project for school where I'm using flex sensors and converting that into words on an LCD (similar to the signing glove if you're familiar with that). I ran into a problem since the ...
0
votes
1answer
89 views

Nodemcu ESP12-E (ESP8266), Can I reprogramming when the UART pins are defined as GPIO?

I wonder if there may be any problems using the pins that the UART are using as GPIOs, if now I want to be able to reprogram the circuit? (Of course I will detach the ESP12-E from the mainboard before ...
0
votes
3answers
60 views

For Arduino Uno it is possible to use the digital pins with PWM to read analog data, is this also possible with the Wemos D1 Mini?

I want to read out data from a load cell, for this I seem to need 2 analog input pins, the Wemos doesn't have this. In the Arduino I was also able to use the digital pint with PWM, there are also ...
0
votes
0answers
24 views

How to stop and repeat a melody using a button?

How can we make our melody stop when we press the button the first time and repeat the melody when we press the button the second time? // Noterna defineras #define NOTE_B0 31 #define NOTE_C1 33 #...
0
votes
1answer
73 views

What is the maximum number of sensors that can be operated on a single Aurdino unit

I currently have an Aurdiuno uno and a motor driver shield: (http://www.hobbytronics.co.uk/arduino-motor-shield). Now, I would like to run the following mechatronic devices: 3 bi-direction motors, 1 ...
0
votes
2answers
52 views

How can I discard power from a device I want to read from?

I want to read the data line from a device that normally interfaces with a controller. It has 3 pins, 3.3v power, gnd, and data. I don't need the power line since the Arduino will be USB powered and I ...
0
votes
0answers
340 views

NodeMcu SPI boot GPIO 15

On the esp8266 you've got to pull down the pin GPIO 15 to ground on boot. Otherwise the chip won't boot. However, the boards only open SPI interface has it's ChipSelect (CS,SS,..) on the same pin! Now ...
-1
votes
2answers
216 views

How to hook up led matrix 1088AS to a PCA 9685 servo controller? there is a way? [closed]

I'm confused about the pinout, I can't figure out which physical pin of 1088as red led matrix must to hook up to the PCA9685, if there is a way to do this I found this image the final target is to ...
0
votes
0answers
27 views

Serial Communication between ESP-01 and arduino [duplicate]

I want to send sensor data from arduino to esp-01 and it further goes to firebase. And also wanted to send status of water pump from firebase back to the arduino to control motor manually. So what pin ...
0
votes
0answers
69 views

Cannot write pin LOW

All the other examples I've seen have had coding errors where they set a pin LOW in a loop with no delay so that it goes high again right away - but this problem is different, and probably something ...
0
votes
0answers
49 views

MOSI pin not turning low [duplicate]

I have the following code: #include <SPI.h> void initChips(){ SPI.begin(); SPI.beginTransaction(SPISettings(20000000, MSBFIRST, SPI_MODE0)); pinMode(SS, OUTPUT); ...
0
votes
2answers
268 views

What data type are the analog pin labels (A0, A1, etc)?

Arduino Mega I would like to have an array containing analog pin labels something like... int analog_pins[] = {A0, A1, A2, A3}; int num_analog_pins = sizeof(analog_pins) / sizeof(analog_pins[0]); ...
0
votes
1answer
154 views

Mini ethernet shield pins don't have SI

Please somebody who had the same issue help me. The question is how to connect this Mini Ethernet shield to an Arduino. The main problem is the pins that my shield have or haven't; my current ...
3
votes
1answer
174 views

Cannot set MOSI pin low even after ending SPI

I'm building a battery operated device and must shutoff MOSI pin during sleep because it leaks current through the SD card if I don't (about 400 µA). Problem is, it won't stay off. I've looked at ...

1 2 3 4 5 8