Omega 2 - Ethernet without Ether dock?
@ccs-hello the easyjack is just a RJ45 connector which can be soldered to - is it not? or is there more to it? for my application I am happy to terminate to screw connectors, which may simplify things for my application. I am purely concerned with what the safest way is to connect the 2 pairs of wires within a CAT5 cable to the ethernet pins of the Omega2
and I am still not clear what is meant by C.T.?
Is this not sufficient for what I would need? with 51 ohm resisters and 100 nF ceramic capacitors?
Example of what's inside:
luz last edited by
Without the transformers, you'll create direct DC connections between Ethernet cable and the Omega2. You might get away with that because the other end will have a transformer, but probably impedances are wrong and if you pick up any significant DC voltage (e.g. a PoE capable switch) on the cable, it will fry the Omega2. So I'd say - definitely not recommended.
I thought I was missing something... I was hoping to get away from the transformer chip to simplify things / lower costs...
seems the cheapest jack I can find here is the following:
Bel Stewart MagJack SI-60002-F (no LED indicators)
of if you insist on the LED's - and want an easy to prototype option, check out sparkfun - RB-Spa-1054
I'll try make time to draw something up later, hopefully help a few other people out with similar needs that might be as new to this as I am
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Tx C.T. and Rx C.T. tied together then go thru a cap to Ground.
There is no need to connect to Omega 2+ side.
Note that EasyJack is not a common part to get in a regular electronic store.
Not that regular but I think pretty available. For example, HR911105A. I got some from Ebay, ca USD4.5 per 5pcs:
Didn't have time yet to check them out.
I found much more difficult to find a human solderable solution for the USB protection circuit and ended up purchasing individual diodes.
luz last edited by
The main advantage over the Bel Stewart is that it has the pins for PPoE (passive power over ethernet, i.e. DC+ on 4/5 and DC- on 7/8). And it's even less expensive.
I checked the Hanrun HR911105A module in the meantime and it works without any issues. Direct connection (T to T and R to R, not a cross-over).
After all the wiring is done, for a quick test, the network configuration file needs to be edited as per this document:
and if all was done correctly, the ethernet port should start acting as a WAN if (and Omega as a hot-spot).
Really interesting... here is a link for Hanrun model volume purchase, $0.60/unit:
What does CT stand for? Not "coil turn(s)"?
What output pins are used for DC +/- on your HLJ model?
Can we do PoE on the Hanrun model too? Same pins?
Hanrun looks complete with resistors and caps, so no external components needed, I assume? But your model datasheet seems to miss the resistors and caps?
- What does CT stand for? Not "coil turn(s)"?
Here is related to an Ethernet magnetics:
CT is a contact made to a point halfway along a winding of a transformer (or an inductor).
@Marcin-Debowski Don't send PoE through that han run mag jack, the resistors inside will burn. Or, you can use a PoE injector/splitter, so you remove the DC power from the cat5 before it gets to the magjack.
These EasyJack, SmartJack, ... have multiple variants (suffix of the part number) for different purposes.
For PoE application, find the right one with the proper part number.
Any chance you can send me the wiring diagram?
I am using the same in my design but cannon make it work.
@Kjell-Sundby For example this is the magnetics of the Seeed Studio's Breakout for Linkit Smart 7688 v2.0 board:
P2 to ETH TX+
P3 to ETH TX-
P4 to ETH RX+
P5 to ETH RX-
GND to GND
This is working well with Omega2(+) and any identical magnetics should work too.