P1 modules

WiFi versions


This is the very first wireless version I’ve made. It’s designed to work as a simple serial-wireless bridge with esp-link from Jeelabs. The idea is to pass the P1 telegrams via the wireless network to a server somewhere else in the network. This can be mounted as a pseudo tty with socat or ser2net.

The latest version of DSMR-reader (v4.1 and above) has the option to connect directly to an web socket .

More information about esp-link can be found here.

Wemos v1

Because the first compact model isn’t easy to flash without some wires and knowledge, I’ve decided to make an easier model, jet less compact. It’s the same as the compact, only easier to flash, as it has an USB header of the Wemos itself. This wireless model is also for those who haven’t got DSMR 5, this model can be powered from the USB port .

WARNING!!! Before using this module, make sure to check the jumper underneath the Wemos. As default, I place the jumper half on the pins (so on one pin and not both). 

Jumper closed
Jumper closed means that the power from the P1 (via this jumper) is connected to the board. When using DSMR 5 and power from the P1 port, the jumper should be closed (on both pins).

Jumper open
Jumper open means that the power pin (1) from the P1 port is disconnected to the board. Therefor you have to power it via the USB port. When powering via USB port, the jumper should be open.

The reason is that I’m not sure what happens when there’s put external power on the P1 port. The data lines are galvanic isolated. Yet I couldn’t find anything about this for the power supply. Adding a diode could solve this, yet the power drop from the diode could make the ESP unstable, as the onboard 5v -> 3v3 converter itself needs at least 1.2 volt.

More information about esp-link can be found here.

Wemos v2.0

The latest update for the Wemos version (fully explained on my blog section), is using a logic inverter (explained earlier for the ethernet version). Version 2.0 is the same as version 1.0, only with the logic inverter instead of the BS170 mosfet inverter:

More information about esp-link can be found here.

Wemos v2.1 (current wifi model)

Version 2.1 is the same as version 2.0, only more compact and the Wemos soldered onto the PCB to make it sturdier for sending it via de mail (more here). It looks even beter with the Wemos D1 mini Pro on it:

To flash it, the jumper must be removed (disconnect the logic inverter to the Rx input). While using it, the jumper must be closed/connected.

More information about esp-link can be found here.

Ethernet versions


This is the very first model I’ve designed and made. The idea was/is very simple. Get the power and signal out the P1 port, invert the data and put it into the USR-TCP232-T2 ethernet module. Read the full story here. Unfortunately there is a minor design fault: The P1 header should be on the other side, same as the ethernet port. But it worked like a charm. The USR comes default with a fixed ip-address instead of DHCP (which I prefer). Every module I sold, I had to change the ip (which isn’t hard, only takes at least 10 minutes each time). Thats why after a short time I tried another model: the Eport-E20, which is smaller, compacter and comes default with DHCP as network setting.

Eport E20 v2.0

Model v2.0. This model is with the Eport E20 instead of the USR-TCP232-T2. The whole build and design story can be read here. This module is much smaller/compacter and easier to get on AliExpress. The USR’s where harder to get, unless you paid double the regular price. That ain’t gonna happen of course 😁

Technical information can be found here.

Eport E20 v2.1

Eport E20 version v2.1. I noticed that there was a lot of request from DSMR 2/3/4 users/owners. Those ports aren’t capable of supplying enough juice on the P1 port and needed external power. So I decided to make some modifications to the design and made model v2.1. It’s the same as v2.0, except I’ve added an USB C port to it for powering it via external source.

Technical information can be found here.

Eport E20 v2.2

Meanwhile I also learned about another single channel logic inverter, which I really liked to try. And that’s where model v2.2 was created. Both models v2.x are the same in functionality and looks. The only difference is the inverter and some extra capacitors for more stability.

Technical information can be found here.

Eport E20 v3.0

For a long time is was thinking about redesign the ethernet P1 reader. I wanted to get rid of the “ugly” jumper on the board. Therefore I’m using a dual anode and common cathode diode to make sure the power between USB and P1 stays separated.

I was playing with the thought of moving the RJ12 header to the other side. Previously designs didn’t have that as I was designing within the limits of 10x10cm (and get as many as possible pcb’s out of each square). While placing the items on de pcb, I saw a opportunity to squeeze the RJ12 header to the other side.

Technical information can be found here.