Questions tagged [sd]

64 questions
3
votes
1 answer

Long freezes at the beginning of sd card transfer

I am creating an accelerometer data logger that writes data to sd card. After some sort of "warm-up" everything works perfectly for at least ~15 minutes (which is what I have tested so far). However, during the first few seconds there are some…
oliver
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3
votes
2 answers

How does one set attributes for SD files?

How does one set file attributes, e.g., creation date, for a file being created on an SD?
KC Tucker
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1
vote
2 answers

Can I read from a memory card with three pins?

I have a project where I have three pins to use and I just realized it would be better to use a memory card than replacing the code each time. I'm building a Arduino with a push button. Press the button and it sends keystrokes to the connected…
Andreas
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1
vote
0 answers

Getting wrong value from sd card

I stored "28328630" in sd card but at output i getting wrong value. on serial "5566" getting this value. #include "HX711.h" #include #include #include #include int data = 0; int curr_rate = 0;  //…
Ravinder
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0
votes
1 answer

Datalogger with interruputs

I'm trying to do a data logger. Writes into SD card has to stop when millis()=1000. Maybe I have a problem between millis() and my interrupt, because datalogger doesn't stop after millis()=1000. I'm working with Arduino Mega. #include…
0
votes
1 answer

Write char array containing new line to SD card

How do I a buffer (char array) containing new line character to SD card using SdFat? I tried: File myFile = SD.open("test.txt", FILE_WRITE) myFile.write(buffer, BUFLEN) but I get this instead: 0000 0000 0000 0000 0000 0000 0000 3337 3837 3838 3937…
Dzung Nguyen
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0
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1 answer

How do I load an image using fopen()?

I am trying to write a program that fopen()s an image so I can use it later. I've wired my SD card adapter exactly the way shown here: [![enter image description here][1]][1] And I'm using the following code to fopen(): FILE *streamIn; streamIn =…
-1
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1 answer

SD card reader and lcd display

I have sd card reader and lcd display. I want to display bitmap with u8g2 library. My bitmap looks like: 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x3f, 0x00, 0x00, 0x00, 0x80, 0xff, 0xff, 0xff, 0xff, 0xff,…