7
votes
Accepted
EEPROM.get returns bad data
You are saving a String object in EEPROM, which is useless. A string
object does not store the contents of your string. Instead, it just
stores:
the memory address where the actual contents (the ...
- 44.3k
5
votes
Is it possible to use extra AVR Flash memory as non-volatile EEPROM-like Flash memory storage?
Yes you can. This Arduino IDE add on lets you make calls to code store in the bootload of memory so you can make changes to the flash memory.
https://majek.sh/en/writing-to-internal-flash-on-arduino/
...
- 2,423
5
votes
Accepted
Is it possible to use extra AVR Flash memory as non-volatile EEPROM-like Flash memory storage?
The answer is "yes, you can use extra AVR Flash memory as non-volatile EEPROM-like Flash memory storage, very similar to an STM32 microcontroller."
One of these days I'm going to write an Arduino ...
- 1,369
5
votes
Accepted
HTTP-POST returns 400 when posting a value from the sensor
Your line
int httpResponseCode = http.POST("{\"amount\":\"total\"}");
is not doing what you think it's doing. You're not placing the contents of the variable called ...
- 106k
4
votes
Using a Micro SD card for data logging, bad idea? Reliable?
We've been maintaining a network of loggers (60+ currently deployed) using SD card connected directly to the SPI pins (see: http://www.mdpi.com/1424-8220/18/2/530 for details) and our experience is ...
- 111
4
votes
How to increase SD card write speed in arduino
Avoid the handshake getting a buffer!
Use
SD.write(buf,size);
Hi every one, I'm working in a project with the same issue. I was following the same steps of yours and got exactly the same numbers. I'...
- 41
4
votes
Accepted
How to connect 70 analog sensor to a single Arduino (Mega or Uno) device?
There are fairly inexpensive chips called "analog multiplexers" which let you choose one input out of a range (8 or 16 is typical). You could take the reading, then switch to a different input, and ...
- 38.7k
4
votes
Writing to sd card with a sampling rate 50ms or less? I have a sketch that writes to sd every 1s but jams at faster sampling rates. Please help?
Some tips:
Do not open the open and close the file in every loop sequence (I think you can use the flush command to save/update the file.
Do not save strings, but save the raw data and pulse string. ...
- 13k
3
votes
Accepted
Grab keys from an ordinary USB keyboard
As suggested in the comments, you have two options:
As suggested by Majenko, you can use the Arduino USB Host Shield:
Alternatively you could use a PS2 keyboard instead (as suggested by Gerben). ...
- 3,198
3
votes
Accepted
Data loging while browsing a menu on LCD shield
The key is that the menu code must never wait as the operateMainMenu() function does. Instead, it has to test the buttons, do a required task, if any, quickly, and return. This means it depends on ...
- 15.3k
3
votes
Accepted
How to manage two alarms with one interrupt?
Consider it is good practice to leave as little code in an interrupt as possible. In this case, as the time in question is much greater then how often the loop() function is called, setting a single ...
- 7,470
3
votes
EEPROM.get returns bad data
Just to have the full working code, I ended up with this:
#include <EEPROM.h>
char serial_characters[] = {"ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"};
// 7 chars for serial and one for string end '...
- 252
3
votes
Accepted
Where is the Arduino IDE log file located? Not the Serial Monitor
There is no log file. Instead you need to turn on both "compilation" and "upload" under the "Show verbose output during:" option in Preferences.
This will give you far ...
- 106k
3
votes
Accepted
how can I delete contents of an SD card in arduino?
To remove a file use SD.remove("datalog.txt");
SD library's FILE_WRITE is O_READ | O_WRITE | O_CREAT | O_APPEND so it would append at the end of the existing file.
to start with an empty ...
- 18.2k
3
votes
Can I use Data Logger Shield with Arduino Sensor shield V5.0?
The 'data logging' shield by Adafruit and Deek Robot has two devices.
First device is the SD card which uses SPI bus. Every SPI device on the SPI bus has to have a select pin CS. On this shield the SD ...
- 18.2k
3
votes
How do you deal with balancing the limited storage of Arduino with the decrease in speed if you just print everything as it gets measured?
This is all about choosing the right tool for the job.
At the moment you're trying to fit 50 clowns into a mini. While there are ways of doing it (by extending the "mini" outwards with extra ...
- 106k
2
votes
External Flash Memory File System
I don't think you need a file system: that is usually needed when you want to manage many files. Your weather data log sounds like a single file.
What you seem to need is to access EEPROM as a stream,...
- 1,278
2
votes
External Flash Memory File System
This lib offers a means of reading and writing ASCII arrays to flash devices. This would be a simple solution for such a data logger requirements. It's ASCII orientated.
https://github.com/schinken/...
- 21
2
votes
Accepted
What is the point of a adafruit data logger
Are you referring to this?
That is a shield that has an SD card interface (with appropriate level-shifting for the SD card) plus a real-time clock.
The rest is "prototyping" area for you to install ...
- 38.7k
2
votes
Grab keys from an ordinary USB keyboard
I am able to use this library: https://github.com/techpaul/PS2KeyAdvanced and USB's data +/- connected to pins 2+3 of an arduino to read keys on standard keyboards.
keyboard.begin( 3, 2); // D3= data+...
- 1,037
2
votes
Accepted
Uniform timing when using Arduino for data acquisition
the ADC is LTC1859 and triggers on the slave select falling edge.
No, it doesn't. Here is a link to its datasheet. It has a pin
labeled CONVST, for “conversion start”. According to the section Pin
...
- 44.3k
2
votes
Accepted
Interfacing AD7606 with Arduino Due. How to data-log?
You can use python on the command line to log your serial monitor output. This is described here. The script below has a baud rate of 250000 but can be set according to how you program your arduino.
...
- 168
2
votes
Arduino log file directly to file
Any serial terminal emulator application can connect to the Arduino. Select one that has log-to-file capability and open its log file after you've connected it to your Arduino's /dev/tty... device.
...
- 15.3k
2
votes
Conflict between SD card shield and accelerometer
Based on the information that you've provided, it's quite likely that your problem lies with how your SD card and accelerometer connect via the SPI bus.
The problem is that a lot of Serial ...
- 1,032
2
votes
Fast data logging
Read the values into an array big enough to store them
Write the array with the write(const uint8_t *buffer, size_t size) method.
Each write then gives you a block of binary data (512 values, 1024 ...
- 106k
2
votes
Accepted
Writing to sd card with a sampling rate 50ms or less? I have a sketch that writes to sd every 1s but jams at faster sampling rates. Please help?
So it turns out the actual problem was this line of code
if ((millis() - oldTime) == 50) {
it needed to be changed to
if ((millis() - oldTime >= 50) {
I really appreciate all the help everyone ...
- 115
2
votes
How to manage two alarms with one interrupt?
The typical solution to this type of problem is:
In the ISR set a flag to indicate an RTC interrupt has occurred.
In the loop check the flag and if the set:
a) Read the alarm flags from the RTC,
b) ...
- 7,979
2
votes
How to link a computer processor to an Arduinno on a board?
It sounds like you need a lot of compute power. You can either put the sensors and AI on one device (and @majenko's suggestion of a Raspberry Pi would be a direction to pursue) or you need two devices,...
- 15.3k
2
votes
File created, but not logging data
Thanks for all your help. I managed to log data in the SD card including date and time. The new code is the following:
#include <SPI.h>
#include <SD.h>
#include "RTClib.h"
...
- 41
2
votes
Accepted
Reproduce simulated temperature data with Arduino
You can use an array to go through the times.
Create a struct with the fields time and temperature (you should think about saving time as unix epoch, meaning seconds since 1970, so that you save ...
- 16.5k
Only top scored, non community-wiki answers of a minimum length are eligible