Custom made ethernet gateway based on atmega128

[axillent]

it got been print-cased)

this is in progress the development of gateway #2

[axillent]

instant made PCB is ready to be soldered

[marceloaqno]

Great Job! What are you using for the power supply?

[axillent]

@celonunes thanks!

on the photo you can see a black square part, it is a transformer
after transformer i have a bridge rectifier, one step-down based on MP2359 to get +5V
and other step-down base on NCP1529 to get 3.3V from the +5V

[axillent]

the schematics

[RJ_Make]

@axillent I just noticed 2 push buttons in the schematics? Is one a reset?

[axillent]

@ServiceXp atmega128 provides 53 I/O pins, I had to use at least some of them)))

I have no exact application for both buttons but probably will use them somehow in extended version of the Ethernet Gateway

[epierre]

why not use a photon ? it is $19 and already has the wifi ?

[axillent]

@epierre cortex is a nice thing but currently not supported by Mysensors. Do you want to add the support?

we are looking for the gateway based on ESP8266, it is just $4 board including WIFI and powerful MCU

[epierre]

@axillent I'm currently supporting my scripts on both arduino and spark.io to avoid everybody reinventing the wheel. Hopefully spark.io is more a hardware provider, meaning they design and implement hardware of their own they afterward sell, or sponsor through indiegogo. They also already have a could cum IFTTT already working.

Currently mysensors is too much linked to the vera although it is opening up. With a gateway that would be automatically wifi or wired, as you plan to do, that would change this.

I understand the approch for a cheap board, but I guess that you would need more components in you BOM that just the ESP8266 plus some soldering on a board ? (I don't speak of this nice russian transformer ;-) but that would kill many people in between just soldering, no ?

[axillent]

@epierre nice value arduino provide is that you can do nice things with low entry barrier and without soldering
Mysensors is intend to use this value as much as possible.

"Solder or not solder" is a personal decision and mostly subject of the fan.
At least for me it is fan
as for device from this topic it is not share of the schematics, it is just share of a fan)
russian transformer is part of it (i have a german one but it is too weak for this particular application)

as for ESP8266 - 4$ is the cost of a ready to use module. The only missing thing is radio, you will need to connect 5 wires to radio,
your BOM is simple - ESP module, nordic module and power supply
should be simple even without a special Mysensors board.
I see a good potential here

also I see a good potential on a future network topology discussed in a separate thread, I'm going to test myself an installation with multi hardware layer multi gateway MySensors network

[epierre]

@axillent which is something I actually do with all deversing into domoticz (vera, mysensors, spark core, webcam), and have an uniformized access through imperihome.

I'm very interrested about the wifi capacity if we cannot achieve some level of security within rf24.

[axillent]

I got an idea to improve my gateway by adding 433MHz receiver
I'm succeeded by adding it into the same dimension

As discussed with @hek it will be other version of EthernetGateway sketch able to handle both NRF24 and RF433 reciever

Just a small change to schematic

[Anticimex]

@epierre About security within rf24 we are close. I have implemented and verified HMAC-SHA256 signing. I just need some more time to implement support for a pure software-alternative to the ATSHA204 as well and my "offering" will be complete. Check the security thread (I will post my update there once finished).

[epierre]

@Anticimex This is good news, that would make us a bit safer... next step will be two ways SSL encryption ;-)

[Anticimex]

@epierre ha! Well, whoever wants encryption, feel free to do it :) I see no need so I'm skipping that though. I am fine with somebody potentially reading the sensor values and instructions I transmit. What concerns me is if somebody could fool my system and inject their own commands. But with my signing, I challenge anybody to try ;) (and I publish full sources)

[axillent]

I made a version with RF433 receiver, I'm able to fit it into the same size PCB & same size box

will work on the new code to support RF433 sensors. The idea is to use ID=254 for the single node which will holds all RF433 sensors as it's children. I will need to manage a special inclusion for RF433 sensors. I have two buttons and 3 leds. This probably will be used to select & indicate sensor type during inclusion. Sensor type and child ID will be stored in gateway EEPROM. For the controller sensors will behave as regular motions / fire / door / water leakage / etc. sensors

I have all this sensors connected to simple GSM alarm system. The advantage to connect the, to mysensors is a reuse. All sensors will be working simultaneously with alarm and mysensors

[RJ_Make]

@axillent Were did you get those screw inserts?

[axillent]

@ServiceXp said:

@axillent Were did you get those screw inserts?

all were purchased on aliexpress

[RJ_Make]

@axillent Would you happen to have links?