SD card module


i'm doing a project which should store the value of voltage and frequency of the household main supply for about a month . As from what i have came across, i will probably need to use a SD card module for that purpose . Since i have bought a TFT 1.8 inch display which consist of a SD card slot can i use that one for the purpose of data writing as well?


Grumpy_Mike: Yes.

Grumpy_Mike, That is a pretty terse response. :)


But accurate and answers the question.

Grumpy_Mike: Yes.


Grumpy_Mike: But accurate and answers the question.

When someone writes a question a paragraph long, and the correct answer is one word, I always wonder what they thought their question was.

I hope to OP will expand their statement to include a question of similar complexity.


The question might be "how do I use the SD card on a display shield" but that was not asked. If it were asked then the answer would be slightly longer.

Just like using any other SD card attached to an Arduino.

Assuming Google is not broken for the OP it is all he needs to know.

I'll assume you want to use that SD card writer, so I will refer you to my YouTube video #22 "Using an SD card to log data - and how to improve the reliability!" which deals with a standalone SD card reader but may well be much the same as the one you have.

The improved 'reliability' element in that video refers to the fact that it will not detect removal of an SD card as it stands (even though the hardware supports it) but that hardware mod may not be required on your actual (as yet, unspecified) SD card module.

Anyway, have a look at the video, if nothing else it shows you how to write stuff to it. URL is in the footer of this post, have fun. :)

we can interject our ideas all day. how many times a second does the data get logged ? that would yield answers about memory size and such and would or should branch off into discussions about not recording data that is in the expected tolerance. why bother data logging a hour of 230 volts of 6.125 amps when you really want to know when the amps went from 2.1 to 6.1 and when they dropped again ?

household, to me, means single phase, ergo, only needs to monitor one sine wave. that is running at 60hZ or 50hZ ? and you have to have about 4 times the data points in order to know where you are, so figure 256 points a second ? how many seconds in a month ? or, do you calculate voltage and show RMS ? and amps, and time ?

or, was the thought about using I2C or SPI and data storeage and dumping in conjunction with writing the display ?

or, just maybe, the question was if the attached SD socket is addressable by the Arduino ? as in is the SD socket addressable by the Arduino ? sort of "is it read only, or read and write and is it only for use by the display..."