Arduino Forum

Products => Arduino Due => Topic started by: weird_dave on Oct 05, 2016, 11:17 am

Title: Due with Ethernet Shield 2 (without POE module)
Post by: weird_dave on Oct 05, 2016, 11:17 am
It looks compatible but I might have missed something, can anyone confirm?
Title: Re: Due with Ethernet Shield 2 (without POE module)
Post by: ghlawrence2000 on Oct 05, 2016, 04:54 pm
I might have missed something, can anyone confirm?
I can confirm you missed a whole lot of detail about exactly what you are asking!!
Title: Re: Due with Ethernet Shield 2 (without POE module)
Post by: weird_dave on Oct 06, 2016, 02:22 pm
I didn't think it was difficult to understand what I am asking. Is the Due compatible with Ethernet Shield 2? Do you want me to explicitly state that I mean physically, electrically, philosophically?
If I limit my question to less than everything, I might miss a key part of the question/answer :)
Title: Re: Due with Ethernet Shield 2 (without POE module)
Post by: ghlawrence2000 on Oct 06, 2016, 03:39 pm
Ambiguous answers to poorly formed questions are available on Google, you may of heard of it?

1) Does it physically connect to the Due? Yes

2) Is there a suitable library? Yes

3) Does the library support multiple SPI devices? Difficult to say without specifics!

4) Can I sign into Facebook? I guess but haven't tried personally

5) Can I recieve an atomic clock time signal via NTP protocol? Yes

6) Can I run a webserver? Yes

7) Crystal ball overloaded from guessing what the hell you MIGHT want to do!!!!
Title: Re: Due with Ethernet Shield 2 (without POE module)
Post by: weird_dave on Oct 06, 2016, 03:57 pm
Nothing more than connect an Ethernet shield 2 to a Due and use the appropriate libraries (obviously). Nothing more, nothing less, no guessing required. This was a simple compatibility question.

I did try googling for the answer, didn't find it and figured the forum would be a good place to ask.

If I had asked (on an AV forum) if ABC blu-ray player was compatible with DEF TV, I wouldn't expect to provide information on what disks I might be using and how many people are watching.

After mentioning electrical compatibility in my previous reply, I note that this is still unanswered...
Given that the Due is 3v3 and standard Arduinos are mostly 5v, for which most shields are primarily designed, this is probably the most important compatibility issue.
Title: Re: Due with Ethernet Shield 2 (without POE module)
Post by: ghlawrence2000 on Oct 06, 2016, 04:07 pm
Given that the Due is 3v3 and standard Arduinos are mostly 5v, for which most shields are primarily designed, this is probably the most important compatibility issue.

Not so, if you wish to use UDP to handle 400KB/s then it falls over, but low volume traffic is ok, persuading it to work with other SPI devices (Flash IC, SD Card) can be great fun!! Ping, NTP, UDP all at the same time? Good luck with that. 
3.3V is seen as a logic high by 5V devices so yes, you can stick it on the DUE, the other way round however and things tend to go pop or fizz or bang......... 
Title: Re: Due with Ethernet Shield 2 (without POE module)
Post by: weird_dave on Oct 06, 2016, 04:40 pm
Not so, if you wish to use UDP to handle 400KB/s then it falls over, but low volume traffic is ok, persuading it to work with other SPI devices (Flash IC, SD Card) can be great fun!! Ping, NTP, UDP all at the same time? Good luck with that.
Are these Due/Eth2 specific compatibility issues or general problems?


3.3V is seen as a logic high by 5V devices so yes, you can stick it on the DUE, the other way round however and things tend to go pop or fizz or bang.........
Exactly, if there a 5v output from the shield pins connecting to the Due that I've missed, the magic smoke may get loose, hence my association with the importance of the electrical compatibility.
Title: Re: Due with Ethernet Shield 2 (without POE module)
Post by: ghlawrence2000 on Oct 06, 2016, 04:49 pm
Are these Due/Eth2 specific compatibility issues or general problems?
No idea, only used it on a DUE.
Title: Re: Due with Ethernet Shield 2 (without POE module)
Post by: weird_dave on Oct 06, 2016, 05:18 pm
OK, that's good to know :)
Now that the general compatibility is sorted, I can move onto the next phase of feasibility (or adjust my expectations accordingly).
One of the projects I'm looking at using this for will need to send UDP packets with 50-100 bytes of data every 1ms, this looks possible (it won't have to do much else, it will receive a few bytes every 1ms as well).
Have you pushed the SPI speed successfully to get better throughput?
Title: Re: Due with Ethernet Shield 2 (without POE module)
Post by: ghlawrence2000 on Oct 06, 2016, 05:26 pm
To get it to play nice with Flash and SD, I had to go for clk/3 =28MHz. 42MHz seems fine if it is the only device.
Title: Re: Due with Ethernet Shield 2 (without POE module)
Post by: weird_dave on Oct 06, 2016, 05:53 pm
Wow! Wasn't expecting speeds that high :) I guess the SPI link is quite short. Ta :)