A sequence of characters -- including letters, numbers and symbols -- often used for representing information in a human-readable format.

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1answer
39 views

Reading a 10-byte buffer out of a PROGMEM string stored in a string table

I'm storing a large snippet of text in three separate PROGMEM char arrays: const char script1[] PROGMEM = "...."; const char script2[] PROGMEM = "...."; const char script3[] PROGMEM = "...."; The ...
-1
votes
0answers
15 views

how to configure arduino to use utf8 serial transmition

am working with and Arduino and a SIM900 modem, so far am able to send sms with no problem, but I would like to use utf8 format for the content of my message.... how can I configure my modem to do ...
0
votes
1answer
28 views

Why is my Serial port not printing the right output?

am working with and Arduino nano and according to this, I can append strings to numbers by doing: stringThree = stringOne + 123; but when I do: sensorValue = analogRead(A0); String x1 = "{\"Volt\":"+...
0
votes
1answer
59 views

Using StringStream in Arduino sketch

I learned about StringStream today at work. #include <iostream> #include <sstream> #include <stdio.h> #include <string.h> using namespace std; char* getSql() { float ...
0
votes
1answer
12 views

Using strings inside mBlock extensions code

The following question is about a 3rd party Arduino programming enviroment mBlock and creating extensions for it. I hope that there are some of you out there, who are fammiliar with it. I was ...
-1
votes
1answer
53 views

Why is integer-to-string not working in this sketch?

I am using a Pro Mini to read analog values and to send them via serial. Goal of the sketch is to stream these values to Serial as fast as possible, to obtain a steady stream of at least 1000 ...
0
votes
2answers
36 views

Push to 2D array (log) but last value pushed is everywhere

I have this simple that is supposed to keep a log for me with a fixed number of entries. When I add to the log the oldest replaced is by the second oldest etc and the new entry added. Except when I ...
0
votes
1answer
35 views

String use in arduino IDE (this question for understanding) [duplicate]

I'm using arduino several month now, And i don't understand when i can use the arduino object of String. I'll explain, I read a lot and the it's look like that this object is a good way to read/write ...
0
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1answer
56 views

Storing latitude and longitude floats as chars with specified precision

I am receiving lat and long data from a GPS and want to store these numbers in the middle of a sequence of chars. E.g. lat = -23.123456 long = 135.123456 I am after something like "Your coordinates ...
0
votes
1answer
35 views

How to store a string in an object and retrieve it safely later?

I'm writing a program where I will be able to toggle between multiple banks, and each bank has 4 presets on it. Right now, I'm trying to give each preset a name that is assigned on creation. I have ...
0
votes
3answers
55 views

How do I send a string from an Arduino Slave using SPI?

I have an Arduino Uno acting as a master with 3 Arduino Nano's acting as a slaves. Looking at this example: http://www.gammon.com.au/forum/?id=10892, it tells me how to send a string from the master ...
1
vote
1answer
43 views

RFM69HCW 915 MHz radio module: Sending a stream of int values rather than char[ ]

I'm trying to send a stream of int values (0-4096) from one arduino to another using an RFM69HCW module. Here's my main code: #include <RFM69.h> #include <SPI.h> #define NETWORKID 0 ...
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votes
0answers
37 views

How to split a string in substring? [duplicate]

I have a python background and know how to do string manipulations there. Coming to arduino (C++) I kind of doesn't feel comfortable doing simple stuff that I know in python because it's more low ...
0
votes
3answers
17 views

Merging strings and constants causing scope errors

I'm getting a few errors when merging strings with constants. Here's the pertinent code... #define STATION_ID ABC123 #define STATION_PASS XYZ987 void loop(){ String path = "/weatherstation/...
1
vote
2answers
85 views

eval() function for Arduino?

I plan to do the following: void setup(){ String term = "12 + (2 * 5)"; int result = eval(term); // eval function (from Python) Serial.println(result); // expecting 22 } However there is no ...
0
votes
1answer
32 views

two dimensional array with 3 characters per entry?

my plan is to create a two dimensional array with 3 characters in each cell. what i have tried: char keys[3][8][8] = { {' ','4','5','6','x','/',' ',' '}, {'x10','7','8','9',' ',' ',' ',' '}, {'...
0
votes
1answer
55 views

Difficulties with raw string literals

I have an application where I would like to include an external multiline script as a const in my sketch. As far as I understand from C++11, this should work: raw_string_literal_test.ino const char *...
1
vote
1answer
57 views

strtok problem while parsing String

Here is my code. The incoming string is "*CRB12344,Temp25,Humidity55,CC5#" I am unable to get value of Temp which is 25 and Humidity which is 55 and CC which 5. It only display the value of CR i.e ...
1
vote
1answer
44 views

Arduino SSCANF stop on comma delimiter

I have the following problem, the arduino is receiving a command like LCD,Display line text one, Display line text two I use an strcmp to match the beginning of the string that works but now I would ...
2
votes
1answer
32 views

Blank.txt at the End of Transmission

I'm using my HC-05 (Master) to receive strings from a sensor (Slave), each string is suppose to have 7 items divided by ',' like so "a,b,c,d,e,f,g". I also have to write these strings in a .txt file ...
1
vote
0answers
83 views

save bytes from Serial into ROM (EEPROM)

i am trying to save an incomming text from serial into the rom of the arduino using EEPROM. I found out that you can only save a byte at once. So i thought i could do it like that: #include <...
1
vote
2answers
32 views

Why do i get additional characters when reading a file through a buffer if buffer size > 15?

This is a follow up question to How to speed up writing a file to a WifiClient? I modified the old code to read from one Stream and write to another which looked like this and worked fine albite ...
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votes
1answer
25 views

Replacing stock String.cpp with smaller version

Hey all I am wondering if it's possible to modify the WString.cpp file to only include the commands that I need for my project since that file is so large. I am using a Digispark arduino that is ...
3
votes
3answers
89 views

How to multiply strings?

I want to have a line like this Serial.println(count*"B"); So if count=6, it would print BBBBBB, etc. Is there anything like this for arduino?
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votes
1answer
46 views

Including string class in Eclipse Neon

Probably basic question but when I type include in class of my arduino project I get only error. How do I properly include this string class?
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vote
1answer
67 views

Serial Communication Not Receiving Entire String

I have an Arduino connected to a pico motor driver that is supposed to take a number of steps for a specific number of triggers that gets from a source (i.e. waveform generator). I've setup the code ...
0
votes
1answer
78 views

Converting uint8_t to String - unexpected result

I'm working on a remote control code for ESP controller. Using ESPwebserver and Fastled. When I try to return a value of an uint8_t, as a POST response, i got strange result here is the relevant code: ...
0
votes
1answer
35 views

check string for specific characters?

I am just wondering if it is possible to check a string for specific characters. For example if my string is String mystr = "test"; and I wanted to check for the letter t at the beginning and if it ...
0
votes
2answers
33 views

Nano resets or freezes on calling a function

I'm controlling a light bulb with my Arduino Nano from serial or RF (via nRF24L01+) and I'm passing the commands as a string. After I get all the variables (3 ints) I try calling the function ...
2
votes
2answers
56 views

Help with a Memory Issue

Below is some code that I'm writing to concurrently run "animations" on the same strip of NeoPixels. When I try to make use of the Serial monitor to control the program functions, I just get a bunch ...
3
votes
2answers
81 views

Understanding memory fragmentation due to char arrays in functions

This is similar to: Is this function subject to memory fragmentation? I am trying to get my head around Memory fragmentation in Arduino's and embedded systems in general. Currently I have a ...
0
votes
2answers
91 views

The most effective way to format numbers on Arduino

I made a big search about how to Format Numbers with the Arduino. I want to format unsigned Longs into a String in this format: "23,854,972". The most of the snippets I found work only with the ...
1
vote
1answer
338 views

Parse HTTP Request Arduino

I am sending a HTTP Request to my WiFi module http://192.168.4.1/STA/ID=HelloWorld/Pass=Testin123 How can I parse above string in Arduino. First I need to check for STA, if it exists, continue to ...
1
vote
1answer
64 views

Declaring literal strings

When I want to write a literal string in Python, I use r before the string (or @ in C#): in [1]: print r'\no esca\pe ch\ara\cters' out [1]: \no esca\pe ch\ara\cters In straight c++ I can use R, but ...
0
votes
1answer
57 views

WebSocket client for ArduinoHttpClient conditional if with readString() incoming data buffer

I'm having issues implementing a web socket on the Arduino/Genuino to procress a string received and do something respectively. I'm using SimpleWebSocket example, edited for my purpose, from the ...
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vote
5answers
526 views

Is possible to concatenate integers?

It's a basic one: I have two values from two different analogRead pins: int val1; int val2; For example, val1 = 10 and val2 = 10. How could I put these two values into a variable val3 = val1 + val2 ...
0
votes
1answer
341 views

Size of String array

I am trying to find out the size of an array like this: String days[3] = { "Mon", "Tue", "Wed" }; Serial.printf("Size of array: %2d\n", sizeof(days)); for (int i = 0; i < sizeof(days); i++) { ...
3
votes
1answer
51 views

Informations lost in a string

At first, I sorry if I make some English faults but I'm French. So, I'm making a connection between a client and an Arduino Uno. I receive all data that I need but when I send a response to my ...
0
votes
0answers
348 views

Parsing GET function + ESP8266 + ARDUINO IDE

I am working on a ESP and making it a simple Http web server. I have successfully ON/OFF the led using the browser. I need to use PWM, instead of Switching the led. As of now When I hit http://192.168....
0
votes
0answers
196 views

Arduino UNO stops working after a while - SOLVED

So I was looking after this problem of course, but I cannot guess what the problem can be. I am using Arduino UNO with a matrix module and it after I upload the program it works correctly always for ...
1
vote
1answer
1k views

How to convert String to Double?

I found the .toFloat() but that's not accurate enough. String StrEx = "57.10598"; float FloatEx = StrEx.toFloat(); Serial.println(String(FloatEx)); //outputs 57.11 Serial.println(StrEx); //...
0
votes
1answer
321 views

how to send large strings (> 100 characters) from arduino serial monitor

I am a newbie to arduino programming. I wish to send big strings which are in range of 100 to 1000 characters to my arduino uno. I saw that arduino cannot read more than 63 characters at a time. The ...
0
votes
1answer
387 views

Remove certain characters from char*

I've got an array of char* with serial data that I'm trying to remove ':' from. I have tried to iterate through the char*, find and remove any colons but it just comes out as garbage. char* espData[...
0
votes
1answer
160 views

Arduino: put string through variable in array

I have a problem and I can't fix it. I'm busy with an java to arduino project. Java writes a string using writeString(); Arduino reads the serial monitor and put the incoming string into a function. ...
0
votes
0answers
496 views

Using Sprintf() to left pad a string?

I've been at this all day, and I just can't seem to wrap my mind around how to use sprintf() to set a width for my string so that my characters are right justified. What I'm trying to do is scooch ...
0
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1answer
784 views

convert String to unsigned long long

i want to convert string for example "68976543210" to unsigned long long(64 bit) in mega2560, do is possible? String x="68976543210"; unsigned long long y=?;
0
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1answer
38 views

error loading an array of strings

I'm trying to have a user enter a series of strings. This is my code. this is my error message - cannot convert 'String' to 'char*' in assignment char* titles[] = {"entry one", "entry two", "entry ...
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votes
1answer
108 views

Strings that always stay empty

I wrote an app that listens on the network for command over UDP and sends back an answer. Whatever I try to put into my answer never get sent. The string is always empty. The following code prints a ...
0
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3answers
61 views

I need to build a char array from two integers

My C is rusty, so please forgive this simple problem. This line works: Tft.drawString("Test",200,200,2,WHITE); But, this has compile errors: String yStr = "Test"; Tft.drawString(yStr,200,200,2,...
1
vote
1answer
229 views

Split string into an array of string

I have a SIM900 module connected to an Arduino Uno, using an AT command for listing the SMS I get this output, how can i split this based on (,) to store each data in an array? AT+CMGL="ALL" +CMGL: ...