memory card/Pen drive interfacing

[Parth86]

This is a weird question in my mind. Have you ever connected the memory card to the controller? or Have you ever connected the pen drive to the controller?
Both are storage device, I have never seen them connecting with the controller. In which situation we will do this

 

[Nigel Goodwin]

It's a fairly common requirement, and I've recently been doing just that - connecting an SD card to a PIC microcontroller.

At this precise moment it's displaying a sequence of photos, other common uses are storage for loggers etc. or for storing webpages on with a small web server, based on an ESP8266 or similar, or for playing MP3's from.

Basically anything which requires either storing, or retrieving, large quantities of data.

 

[dr pepper]

Theres a library for the arduino for sd cards, makes the whole thing fairly simple.
Esp8266 devices which have wifi built in have large amounts of memory onboard, and with the arduino ide you can use it as a sd card.

 

[Pommie]

I use a Wemos mini (Esp8266) as a server and it has 1Megabyte for code and 3 meg for the file system(SPIFF). I have got an SD shield for it but haven't needed it yet.

Mike.

 

[dr pepper]

You can unsolder the little memory chip and put a bigger one in too.

 

[Pommie]

If you get the Wemos mini pro it comes with 16 meg of memory but you can still only use 1 meg for code. The rest can be setup as a 12M spiff file system. Mine should arrive any day now.

Mike.

 

[dr pepper]

I put together an online webpage with 3 graphical fuel giages for the 3 silo's we have at work, somewhere on this site theres a screenshot, the esp acted independantly as a webpage and uploaded the page which was written in javascript,html,css.
All is stored via spiffs in the esp's memory, the guages are updated using ajax.
At first I tried to do it all with an esp and a arduino using At commands to the esp module, but just couldnt get it to work, then I used the arduino ide and prgrammed the esp directly and got the thing to work well with just the esp, no arduino.
Beware the esp8266 01 behaves weirdly when signal level is low, they might have sussed that in firmware now, still a good idea to use the signal level meter in the esp though and detect low signal, also good if you have a project permanently online periodically check the connection and reconnect if its lost.

 

[Pommie]

Beware the esp8266 01 behaves weirdly when signal level is low

I assume that esp8266 01 refers to version 1 and the Wemos D1 V2 is OK or does the problem persist?

Mike.

 

[dr pepper]

Nope the 01 is a different module, I have used the d1v2 but not at long range so I wouldnt know.