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2 answers

Difference between WiFiClient and HttpClient

Apologies if this question appears to be too vague but I would like to know the key differences between these two clients. While WiFiClient comes pre-loaded with Arduino IDE, HttpClient doesn't. Also, to send HTTP commands to a server (XML/JSON),…
LSA747
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Is it possible to infer the length of a neopixel string using 1-wire protocol?

I'have been looking at the AdaFruit NeoPixels recently and am trying to understand how the addressing scheme works. All of the examples I've seen explicitly identify the length of the string (number of neopixel units) and are typically set using an…
Dave G
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At what level does low dynamic memory effect performance?

I have a few Arduino sketches that take 70-90% of dynamic memory. It seems that over 70%, the compiler gives the warning: Low memory available, stability problems may occur. but otherwise I wasn't noticing any problems. Then I uploaded a sketch…
Cerin
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Problem with inaccurate delays between sensor readings

During the last two months I have been working on a project that consists of using a Seeeduino Stalker V2.3, two AM2305 sensors, a TSL2561 sensor, an HC-05 XBee module, a 1,800 mAh 3.7V LiPo, a 7 cm x 7 cm 5V solar cell, and a waterproof suction…
OpenAGRO
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How to do run time calibration for MPU9250?

Does anyone know how to do the run time calibration for MPU9250 ?
Thomas
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6 answers

Difference between data type int and long on Arduino

I was learning to program for a void obstacle robot but when I looked at the code I saw two data types long and int. Int are datatypes that holds -2,147,483,648 to 2,147,483,647. Long are also datatypes that holds -2,147,483,648 to…
roshan timsina
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Arduino CAN SPI Configuration problem

I am using an Arduino UNO along with a Cooking Hacks CAN Bus Module and Multiprotocol Radio Shield. The CAN module is connected to the radio shield which is plugged into the Arduino. I got this radio shield keeping future applications in mind where…
Varun Raman
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3 answers

Are there sensors that can detect the color of an LED?

Are there sensors that can detect the color of an LED? I am working on an Arduino project that needs to detect the color of an LED on an external device. I am trying to identify a light sensor that can be connected to the Arduino's input that can…
StvnBrkdll
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Do I use 3,3V or 5V, when device supports both?

I have a general question regarding the power-supply of the electronic components, that are attached to an Arduino. If I have a device that operates at voltages between 3,3V and 5V (e.g. this RS232 to ttl converter), what is the best way to connect…
Michael B
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Why the 4.7 K Ω resistor in this pitch follower sketch?

I am reading Arduino for Dummies, and I am blocked at the pitch follower exercise. It consists in making a piezo vary with a light sensor. I can't see the point of the resistor (and why 4.7?) in this sketch: Any help for a dummy is appreciated! :-)
seinecle
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Upload with esptool fails with "espcomm_send_command: can't receive slip payload data"

Uploading a sketch to an ESP8266 board fails with: error: failed reading byte warning: espcomm_send_command: can't receive slip payload data warning: espcomm_send_command(FLASH_DOWNLOAD_BEGIN) failed ...or: espcomm cmd: receiving 2 bytes of…
Arjan
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Use large variables without using much memory

I've wired up a dot matrix, and I display characters on the screen by using something like the example code below. The Char_B variable is a global variable in a library used by the Arduino, and displayPixels() is called from inside the library. bool…
user16869
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MFRC522 Only working sometimes

/* * -------------------------------------------------------------------------------------------------------------------- * Example sketch/program showing how to read data from a PICC to serial. *…
Devon Freeland
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4 answers

Converting data between baud rates

This isn't strictly limited to Arduino but I spend a lot of time with serial devices on my Arduino and I'm sure that others do as well: Here goes.. Let's say a device sends three characters [ABC] via serial at 9600 8N1. And let's also say the…
James
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Maximum frequency of digital signal in Arduino Uno?

As Arduino Uno has a 16 MHz oscillator but while running program it has less frequency because some of the processing power is used for running the program. I have used the delay(1) but it is giving me around 500 Hz. My questions: Is there any way…
koolwithk
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