All Questions
9 questions
2
votes
1
answer
1k
views
Converting c string to integer to unsigned char
I'm grappling with types between two different libraries.
The gist is that I'm using the ArduinoWebsockets library to receive information coming from my API that I then want to render out to an LED ...
- 357
1
vote
1
answer
754
views
I can't receive string that I have sent through nrf correctly
I'm using arduino uno and nrf24l01. to monitor sensor data.
But this is the message that master receives:
⸮
this is my slave code.
void monitoring() {
delay(10);
radio.stopListening();
...
- 45
0
votes
1
answer
235
views
Update `char* `
I have a class containing few char* variables:
char* msgTopic = "myHome/MSGS";
char* groupTopic = "myHome/All";
char* errorTopic = "myHome/Err";
but, I wish to have it defined outside the ...
- 1,049
2
votes
2
answers
3k
views
Compute SHA256 of string and output to string
In my Arduino project I want to compute the SHA256 hash of a string and store the result to a string, and do this recursively many times (i.e. compute hash of hash of hash etc...). So my goal is to ...
- 123
3
votes
1
answer
2k
views
How do string pointers work in Arduino?
To the best of my understanding, when I declare
String s = "This is a string.";
what happens is that space is allocated on the stack for a pointer which points to some String object which internally ...
- 33
0
votes
1
answer
7k
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[...
- 3
2
votes
2
answers
16k
views
How can I pass a char array as the parameter to a function?
I am creating a menu for adjusting system variables.
The menu is made up of pointers like so:
char* options4[] = {"hMin1", "hMax1", "refr1", "fSpeed1"};
I want to pass the selected string as the ...
- 87
1
vote
1
answer
357
views
String operators
I have a section of code that I am unsure of what it is doing.
static int bufindw = 0;
static char buffer[4][96];
static char *strchr_pointer;
int result;
result = (int)strtod(&buffer[bufindw][...
1
vote
1
answer
8k
views
How to use String.substring?
I have the following code in which requestLine is always empty and I can't figure out why. request contains a raw HTTP request, and I want to get the first line of the request which contains the ...
- 111