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UnaClocker
11-24-2012, 07:39 AM
Well, when I came up with the idea for this, HWGuy hadn't done his board yet. His board is great, and does what I set out to do initially, so I took mine a step further. But I'm sticking with the TeensyDapter name I came up with.. ;)
This is a Teensy 3.0 to Arduino (Uno R3 style) footprint. It includes an ENC28J60 ethernet chip, and a MicroSD Card slot. Those are both 3.3v devices, so they're well suited to the Teensy 3.0. The Teensy 3 also has plenty of SRAM, which is handy with the ENC28J60 since the TCP stack is software based, so it takes up precious ram.
I created a Teensy 3.0 eagle library, my first attempt at making a library. It seemed easy enough, I'm pretty sure I got it right. I used the Adafruit eagle library for the Arduino footprint, as well as a couple other components. I referenced the Nanode 5 schematic to wire the ENC28J60 and get the capacitor placement right. I think I got it.
I'm going to get a couple of these made at OSHPark to see if it works, I honestly won't be surprised if I got something wrong, but I sure tried to double check everything. If they pass, I'll release the board designs for all to produce at will. If someone wants to review my schematic/board layout before I submit this to OSHPark (probably in the next day or two), I'd certainly welcome it.
Here are some pictures:
56
That's the schematic
57
That's the board layout, in Eagle.
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This is the top, rendered at OSHPark
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This is the bottom, rendered at OSHPark

Paul gets a free copy, if it works. ;)

PaulStoffregen
11-24-2012, 10:43 AM
Here's a few quick questions and comments...

Any chance you might consider the W5100 or W5200 ethernet chips? They're much more compatible with the main Arduino Ethernet library.

How much current does the ethernet use, including any current consumed through the ethernet magnetics? (some chips only spec their own current and don't give you a good idea of the total when actually used with a transformer and cable connected) Even if it's under the 100 mA available, using a separate 3.3 volt regulator to supply the ethernet circuitry might be nice for shields that need to consume some 3.3V power.

Are the drill sizes on Teensy 3.0 large enough? They look pretty small. Usually 0.038 or 0.040 inch diameter is best, for compatibility with normal header pins.

Likewise, do those drill sizes on the DC power jack fit a specific part? Most DC power jacks have rather large pins.

Will the battery holder be able to let the coin cells slip in/out after the nearby Teensy 3.0 pins are soldered?

Also, on the battery connector, you might double check the pinout.

You might want to place the 7805 regulator so it can lay flat. It's probaboy inconvenient to route the wires to that large unused area between the Teensy 3.0 and the shield pins 0 to 12, but it has a huge ground plane that could serve as a nice heatsink. If the 7805 stands tall, it might mechanically interfere with most Arduino shields.

Series resistors between the Teensy 3.0 pins and shield pins might be nice. Most Arduino shields are designed for 5V I/O, so an option to solder a series resistor could allow a shield that drives a pin with a strong 5V output to still work with Teensy 3.0's 3V inputs.

I know it's a pain to work into the design, but you might consider the 6 pin SPI connector. Originally is was meant only for programming the AVR chip, but now several Arduino shields connect the 3 SPI signals from there, rather than pins 11, 12 and 13, since it's the only way to be compatible with Arduino Mega.

These are the things I noticed just a quick look. Let me know before you send the board off and I can take another look.

And thanks for the free board offer! :)

UnaClocker
11-24-2012, 04:35 PM
The Teensy socket pin holes are .03937008", the next size up on the list was .043something".. So they should be big enough, I did take the pin size into consideration when I made that library.
I could use the Wiznet chips, previously they had seemed rather expensive, but I see that they're about $5 vs the $3.50 or so for the ENC28J60, so the price isn't a real issue.
As for the SPI pin, I don't see how I can squeeze it into the board design, I need the Teensy in that spot so that the USB jack is accessible with a shield installed.
I did try to put the Teensy on the other size, but then there's no room for the ethernet and SD Card. The ethernet jack is installed from under the board, so that there's enough clearance for the sheilds. I still have tape on the top of my USB jack on my old Uno because it was too tall for some shields.
Battery connector pinout is good, the top of coin cells is +, so the two outter pads are +, only the one nearest the BATT pin on the Teensy is used. The center is hooked to the ground plane. Unless it's the schematic that looks like I got it wrong? As for clearing the pins, I'd definitely want the CPU removed while you're installing it. And you'd need to have the pins trimmed very flush with the board, but it should fit.
The barrel jack, I usually use PJ-102AH, available at Digikey. The pins are small and fit that profile, which takes up less board space than most of the others with their huge pins.
That's not actually a 7805 regulator, it's like a 7833 or something, it's a 1amp 3.3v regulator. I think it solves several problems. 5v shields won't get 5v, they'll only get 3.3v, so no risk of burning out the Teensy. It also removes the need to run off the Teensy's 3.3v regulator, and gives plenty of current for all the devices. And I had the regulator installed on the back of the board, I should look for a profile that lets it lay flat and bolt down still, but I was trying to save board real estate, as well as allow a heatsink to be installed on the regulator.

Thanks for the feedback, I'll look into switching to the Wiznet chip, and I'll try again to re-arrange the board when I do that.

PaulStoffregen
11-24-2012, 04:51 PM
Ok, sounds good. But you might want to triple check that battery connector pinout....

tochinet
12-10-2012, 02:52 PM
Just a quick question : if you move down the teensy a bit, would you get teh space to add a 20-pin XBee connector on board ? That would create the ideal home gateway !

mkroll
12-17-2013, 02:35 PM
Hi,
have you updated the TeensyDapter according to Pauls hints?
Is there another version of the board available or have you even tested the version you are describing in this post?

Best,
Michael.

stevech
12-18-2013, 01:53 AM
I second the motion on using Wiznet and not the ancient/crude ENC28J60 - which doesn't offload a lot that it should.

I've used 100 or more Wiznet 5100 chip based solutions. The 5200 is newer/better/similar.

PaulStoffregen
12-18-2013, 09:55 AM
Does anyone know of a good library for the ENC28J60 that actually works similarly to the official Arduino Ethernet library for W5100?

HWGuy
12-18-2013, 03:23 PM
from what i read recently in the arduino forum, UIPEthernet is a good in replacement for the normal Arduino Ethernet library.

Arduino board: http://forum.arduino.cc/index.php?topic=178024.msg1483027
github repo: https://github.com/ntruchsess/arduino_uip

PaulStoffregen
12-18-2013, 06:59 PM
Thanks. I had not seen this library yet. It compiles ok for Teensy 3.1. Lots of warnings, but they look harmless. It uses AVR SPI register access, with works great on Teensy 3.X due to avr_emulation.h.

I just ordered a couple cheap ENC28J60s from an Asian merchant on Ebay. I thought I had one, but I just looked in my box of Arduino library hardware and didn't find it. Guess I'll just have to wait a couple weeks until those boards arrive.

CheapB
09-22-2014, 07:33 PM
Thanks. I had not seen this library yet. It compiles ok for Teensy 3.1. Lots of warnings, but they look harmless. It uses AVR SPI register access, with works great on Teensy 3.X due to avr_emulation.h.

I just ordered a couple cheap ENC28J60s from an Asian merchant on Ebay. I thought I had one, but I just looked in my box of Arduino library hardware and didn't find it. Guess I'll just have to wait a couple weeks until those boards arrive.

Does anyone have a list of pin assignment between ENC28J60 and Teensy 3 using UIPEthernet?

Thanks!

PaulStoffregen
09-22-2014, 10:01 PM
Those two ENC28J60 is still sitting in my big pile of hardware to test....

I've been pretty distracted from library testing while developing the audio lib. After the 1.0 audio release, I really should get more of these less-commonly-used Arduino libraries tested and documented.