Use Arduino WebServer with SD card

Projects General Guidance
1

I have read this article:

Can I use the SD Card that this shield has to store data from sensors connected to the Arduino MEGA 2560 R3?

Can I store HTML code to the SD card and each time I access the Arduino Web Server, to get results?

2

Yes.
Yes.

3

What is the maximum SDcard size that it supports?
How can I read the IP that the home router assigns to the Arduino? How to find the mac address?

4

alex5678:
How can I read the IP that the home router assigns to the Arduino? How to find the mac address?

Your router DHCP table should tell you.
Or install Advanced IP Scanner.

5
6

SteveMann:
Your router DHCP table should tell you.
Or install Advanced IP Scanner.

I believe this tool does not scan ports...because it is illegal in my country.

I uploaded this code to Arduino: https://www.arduino.cc/en/Tutorial/BarometricPressureWebServer
But I cannot connect to the Arduino through my browser, although the first 5 seconds it did connect and saw measurements.

edit: I plugged off the ethernet cable, then plugged on. It showed messages in the browser for 5 seconds, when I refreshed the page it disconnected, and continuous disconnected...

I want to make use of a small tft 2.2 TFT SPI screen. How can I use SPI for ethernet + SD card + TFT? Is it possible?

7

alex5678:
I believe this tool does not scan ports...because it is illegal in my country.

Who said anything about ports? You asked about the MAC address.

8

for Wiznet W5x00 you must enter the MAC address in the sketch

9

I can't figure though, after google searching, how I can manage the Arduino to get its IP address every time I change the net plug, and assign it to a different network. I mean it is odd to program it a priori with an IP address. As every device when we connect to network , the router assign to it the IP address. How I do this with Arduino?

Something else, I have occupied the Arduino's SPI with shield's sd card. I need to use 2 more SPIs for different peripherals. I believe I use 3 "SS" and that's it, right?

10

alex5678:
I can't figure though, after google searching, how I can manage the Arduino to get its IP address every time I change the net plug, and assign it to a different network. I mean it is odd to program it a priori with an IP address. As every device when we connect to network , the router assign to it the IP address. How I do this with Arduino?

Something else, I have occupied the Arduino's SPI with shield's sd card. I need to use 2 more SPIs for different peripherals. I believe I use 3 "SS" and that's it, right?

if you use Ethernet.begin(mac), the address will be retrieved from DHCP (if available)

you have Ethernet and SD card on Ethernet shield. Ethernet uses pin 10 as CS, SD card pin 4.

11

I am trying this code, from the tutorial here:

But it continuously prints on the serial:

error opening data.txt

I am using Arduino MEGA 2560 + Arduino ethernet shield with SD card.

I use the CS = 4 for access in the SD card.

Any idea?

12

did you run the CardInfo example?

13

Juraj:
did you run the CardInfo example?

I just ran this example:
https://www.arduino.cc/en/tutorial/datalogger

This is what you mean?

It says that the SD is initialized but it does not store anything in the SD card.

14

alex5678:
I just ran this example:
https://www.arduino.cc/en/tutorial/datalogger

This is what you mean?

It says that the SD is initialized but it does not store anything in the SD card.

in IDE File menu, there is a Examples submenu. every library has a submenu there. see the examples of the SD library and run the CardInfo example.

15

This is what I got:

image_1.jpg

16

me too :-(. it happens. but my was working a minute ago. I have too many wires on breadboard :slight_smile:

https://forum.arduino.cc/index.php?topic=228201.0

17

Juraj:
me too :-(. it happens. but my was working a minute ago. I have to many wires on breadboard :slight_smile:

Don't Format SD cards with OS utilities! - Storage - Arduino Forum

It works!! Thanks! You are amazing...

18

Can I "see" the Arduino's SD card only, to get the file I have stored and copy it to my laptop?? I mean to accept the Arduino's SD card as a usb stick or something..., so as not to need to plug it off from the Arduino and plug it on the laptop and then plug it off from the laptop and plug in on the Arduino.

19

alex5678:
Can I "see" the Arduino's SD card only, to get the file I have stored and copy it to my laptop?? I mean to accept the Arduino's SD card as a usb stick or something..., so as not to need to plug it off from the Arduino and plug it on the laptop and then plug it off from the laptop and plug in on the Arduino.

download it over browser

20

I haven't activated the ethernet function yet. So I search for alternative methods until I achieve ethernet connection...