Cheap ($11) RS232 to Ethernet converter on eBay

Spotted a nice hardware deal? Share here!
Post Reply
User avatar
ThinkPad
Posts: 1754
Joined: Tuesday 30 September 2014 8:49
Target OS: Linux
Domoticz version: beta
Location: The Netherlands
Contact:

Cheap ($11) RS232 to Ethernet converter on eBay

Post by ThinkPad » Tuesday 20 October 2015 19:40

I was browsing eBay and found this little guy: http://www.ebay.com/itm/RS232-Serial-to ... 1839114578

It is a cheap RS232 (serial) to Ethernet device. Seems very handy to me for devices like OTGW or maybe even the smart meter.
The reviews seem quite positive about it: http://forum.micasaverde.com/index.php/ ... 184.0.html

Maybe useful for someone who has his Domoticz server on the other side of the house, or has Domoticz running in a virtual machine (like me).
It needs power (5V or 3.3V, not sure + GND) and RX, TX.

With Windows software like 'Virtual COM port exists'. For Linux you can probably use 'ser2net' / 'socat' or something.


I will search a bit further, i prefer a device with a casing. Otherwise i will probably buy this one.
ThinkTheme - theme for Domoticz
My (Dutch) blog: http://thinkpad.tweakblogs.net - My Domoticz scripts: Bitbucket
I'm not (very) active anymore on this forum as i don't use Domoticz anymore.

idonl
Posts: 22
Joined: Sunday 16 August 2015 20:05
Target OS: NAS (Synology & others)
Domoticz version:
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by idonl » Wednesday 21 October 2015 21:14

cool, thanks for sharing

User avatar
ThinkPad
Posts: 1754
Joined: Tuesday 30 September 2014 8:49
Target OS: Linux
Domoticz version: beta
Location: The Netherlands
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by ThinkPad » Wednesday 21 October 2015 21:23

I think http://www.aliexpress.com/item/FD014-US ... 25678.html ($20,80) is the cheapest device that has a casing.

Or buy this one (USR-TCP232): http://www.ebay.com/itm/USR-TCP232-2-Se ... 1229605057 ($14,14) and stick it in a box yourself. Last one doesn't contain an adapter, but i don't trust the cheapo crappy powersupplies from China anyway...
Since it needs 5V, i think this: http://www.ebay.com/itm/USB-2-0-Male-to ... 1953302398 is useful, you can then feed it from USB (router / old phone charger).

I bought the last one + the wire. Now wait 2 weeks.... :roll:
ThinkTheme - theme for Domoticz
My (Dutch) blog: http://thinkpad.tweakblogs.net - My Domoticz scripts: Bitbucket
I'm not (very) active anymore on this forum as i don't use Domoticz anymore.

Draakje
Posts: 88
Joined: Thursday 22 October 2015 21:14
Target OS: Linux
Domoticz version: 3.5468
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by Draakje » Tuesday 27 October 2015 15:02

Maybe the converter can be power by ethernet (PoE) ?

Of course you will need a switch with PoE support but this will make the power issue less complicated :)
Hardware: Raspberry Pi 3, OTGW, 433MHz Superheterodyne 3310 RF Link
Software: Ubuntu 16.04, Domoticz v3.5468, WiringPi, rc-switch

User avatar
ThinkPad
Posts: 1754
Joined: Tuesday 30 September 2014 8:49
Target OS: Linux
Domoticz version: beta
Location: The Netherlands
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by ThinkPad » Tuesday 27 October 2015 15:08

Not wit the official PoE i think. But i use the passive PoE method for a IP-cam, which works fine:
http://images.eurodk.com/ebay/rfelement ... cheme3.png
Those converter wires can be bought for a few bucks on eBay (search for something like "passive power ethernet injector", it's a set of two wires).
ThinkTheme - theme for Domoticz
My (Dutch) blog: http://thinkpad.tweakblogs.net - My Domoticz scripts: Bitbucket
I'm not (very) active anymore on this forum as i don't use Domoticz anymore.

Draakje
Posts: 88
Joined: Thursday 22 October 2015 21:14
Target OS: Linux
Domoticz version: 3.5468
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by Draakje » Tuesday 27 October 2015 15:23

ThinkPad wrote:Not wit the official PoE i think. But i use the passive PoE method for a IP-cam, which works fine:
http://images.eurodk.com/ebay/rfelement ... cheme3.png
Those converter wires can be bought for a few bucks on eBay (search for something like "passive power ethernet injector", it's a set of two wires).
Same principal :)
Hardware: Raspberry Pi 3, OTGW, 433MHz Superheterodyne 3310 RF Link
Software: Ubuntu 16.04, Domoticz v3.5468, WiringPi, rc-switch

User avatar
ThinkPad
Posts: 1754
Joined: Tuesday 30 September 2014 8:49
Target OS: Linux
Domoticz version: beta
Location: The Netherlands
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by ThinkPad » Thursday 05 November 2015 21:28

I received the USR-TCP232 today. But is very confusing, the software is half Chinese / half English.
And i'm not sure if the device should be in TCP Client or TCP Server mode... I want to 'listen' to my smartmeter from my PC for example, so i think i need TCP Server mode?

I tried with a USB-Serial connected (putty window open) and putty (telnet mode) over IP (device in TCP Server mode), but when i was 'talking' between the left and right window (2x putty), i only got weird garbled values.... so i'm not sure yet how this works.

When typing 'a' untill 'z', it translates to:

Code: Select all

O'NM&L     K%JI$HG#FE"C!
Downside is that you have to fill in a static IP, netmask & gateway. It doesn't seem to support DHCP. Normally i just write down the MAC-address of a device and setup a static DHCP lease in my router, much easier.

Edit: OK, i think it got something to do with the FTDI cable i am using or so (they don't like eachother). When i tie the RX / TX of the converter together, i get a nice 'loopback-result' (each character i type is repeated).
I set the converter to TCP Server mode, on port 23 (default telnet). I will try later with the OTGW or my smart meter.

Edit2: I think it has something to do with RS232 vs TTL. The device seems to be RS232: http://www.usriot.com/Product/24.html while most microcontrollers and the FTDI USB-cable is TTL.
Sheez.... what can i do about that?
ThinkTheme - theme for Domoticz
My (Dutch) blog: http://thinkpad.tweakblogs.net - My Domoticz scripts: Bitbucket
I'm not (very) active anymore on this forum as i don't use Domoticz anymore.

marcelr
Posts: 60
Joined: Friday 22 May 2015 21:10
Target OS: Linux
Domoticz version: svn 2470
Location: Ehv, NL
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by marcelr » Thursday 05 November 2015 23:24

Sheez.... what can i do about that?
Dunno, but following your post I ordered two of these as well, got the message that they're on the way a few days ago. Will hook one up to an OTGW (also on its way ;-)), which has proper RS232. Should work, I guess. Will start testing when the stuff has arrived in Ehv and is assembled ...

grtz,

marcelr
Last edited by marcelr on Friday 06 November 2015 19:41, edited 1 time in total.

User avatar
ThinkPad
Posts: 1754
Joined: Tuesday 30 September 2014 8:49
Target OS: Linux
Domoticz version: beta
Location: The Netherlands
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by ThinkPad » Friday 06 November 2015 8:16

It seems the DB9 connector is RS232 level, but the PCB also has pads to mount headerpins on (RXD, TXD, GND). These pins are TTL-level i think, because there is a Sipex SP3232EEN on the PCB, which does the conversion TTL <> RS232 it seems.

I will try connecting the OTGW / smart meter to these header pins, i hope it works, saves me buying a MAX232.
ThinkTheme - theme for Domoticz
My (Dutch) blog: http://thinkpad.tweakblogs.net - My Domoticz scripts: Bitbucket
I'm not (very) active anymore on this forum as i don't use Domoticz anymore.

User avatar
ThinkPad
Posts: 1754
Joined: Tuesday 30 September 2014 8:49
Target OS: Linux
Domoticz version: beta
Location: The Netherlands
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by ThinkPad » Friday 06 November 2015 20:31

Ok, i managed to figure it out. If you want TTL on this model (USR-TCP232-2), you need to tap into the signal BEFORE it goes into the Sipex SP3232EEN chip

Like this:
Image

I connected the OTGW (without MAX232, so TTL-levels) to pin 9 & 10 and it works like a charm. The header that is on the PCB (with markings GND, RX, TX) is also RS232, NOT the TTL-level you might think.
My next step is to see if i can scratch the coppertraces to that header, and solder a wire from pin 9 & 10 to the header pins. I now have wires from those pins to OTGW, but i'm afraid they might break. The headers are much more sturdier.

I can now connect with Telnet to the IP-address of the device and to the port (i configured 23 instead of the default 8xxxx) and see the serial console. Happy with this device!
ThinkTheme - theme for Domoticz
My (Dutch) blog: http://thinkpad.tweakblogs.net - My Domoticz scripts: Bitbucket
I'm not (very) active anymore on this forum as i don't use Domoticz anymore.

User avatar
sincze
Posts: 729
Joined: Monday 02 June 2014 22:46
Target OS: Linux
Domoticz version: 3.8153
Location: Netherlands
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by sincze » Sunday 08 November 2015 11:46

ThinkPad wrote:Ok, i managed to figure it out. If you want TTL on this model (USR-TCP232-2), you need to tap into the signal BEFORE it goes into the Sipex SP3232EEN chip

Like this:
Image

I connected the OTGW (without MAX232, so TTL-levels) to pin 9 & 10 and it works like a charm. The header that is on the PCB (with markings GND, RX, TX) is also RS232, NOT the TTL-level you might think.
My next step is to see if i can scratch the coppertraces to that header, and solder a wire from pin 9 & 10 to the header pins. I now have wires from those pins to OTGW, but i'm afraid they might break. The headers are much more sturdier.

I can now connect with Telnet to the IP-address of the device and to the port (i configured 23 instead of the default 8xxxx) and see the serial console. Happy with this device!
:D Hero ! well done.
For the moment I'll stick to the TPLINKs 703 I won at ebay for $19 1 year ago.
At the moment I'm experimenting different problems with OTGW however that I should post in a different topic.
Using Pass2php since 2016-12
LAN: RFLink, P1-Port, OTGW, MySensors
USB: RFXCom, ZWave
WIFI: Mi-light Wifi-Bridge, Sonoff, ESP8266, Xiaomi Gateway
Solar: Omnik Inverter, PVOutput
Video: Kodi clients with Harmony HUB
Sensors: You name it I probably got 1.

User avatar
ThinkPad
Posts: 1754
Joined: Tuesday 30 September 2014 8:49
Target OS: Linux
Domoticz version: beta
Location: The Netherlands
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by ThinkPad » Monday 16 November 2015 17:11

I finished the OTGW a few days ago. All components fit nicely in the box. It has been working without a hitch for a few days now, so this USR-TCP232 module is definately recommended!

I said i would scratch the copper pads and see if i could re-route the header pins to the TTL side of the chip instead of the RS232 part, but i just left it like that. I did however secure the wires with hotglue (great stuff for hobby projects hehe), so that they can't be ripped off and demolish the PCB traces.

Finished product:
Image

Image
(Red LED is for flame status of boiler)

Image
(wire and resistor you see is from/to the red LED visible on outside)
ThinkTheme - theme for Domoticz
My (Dutch) blog: http://thinkpad.tweakblogs.net - My Domoticz scripts: Bitbucket
I'm not (very) active anymore on this forum as i don't use Domoticz anymore.

User avatar
ThinkPad
Posts: 1754
Joined: Tuesday 30 September 2014 8:49
Target OS: Linux
Domoticz version: beta
Location: The Netherlands
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by ThinkPad » Wednesday 23 December 2015 10:48

I think it is also possible to make a Z-Wave to Ethernet device with this converter and a RaZberry.

If you have a look at this: https://domotiga.nl/projects/domotiga/w ... e_RaZberry
You will see that the RaZberry boards needs 3.3V, GND, and has RX/TX pins (serial).

The Serial to Ethernet module also has RX / TX pins, so i think you can connect the RaZberry to it (before the Sipex chip, cause it will be TTL i think, not RS232). For the power you could use something like AMS1117 3.3V regulator (or try to find if you can grab 3.3V from the Serial to Ethernet converter).
Then on your client you need to map the TCP/IP port back to a tty* port, and you are done.

Unfortunately i don't have a RaZberry, otherwise i would have tried it :mrgreen: Ideal to place the RaZberry in a location where it would have better range, and having your home automation server on the top floor of your house or so.
ThinkTheme - theme for Domoticz
My (Dutch) blog: http://thinkpad.tweakblogs.net - My Domoticz scripts: Bitbucket
I'm not (very) active anymore on this forum as i don't use Domoticz anymore.

Draakje
Posts: 88
Joined: Thursday 22 October 2015 21:14
Target OS: Linux
Domoticz version: 3.5468
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by Draakje » Tuesday 26 January 2016 18:02

Hi,

I also have bought some RS232 to ethernet chinese stuff. But I seem to be unable to get these things working (I don't even get them powered up)

Do you have any possible pics how you have connected power etc to the device ?

Regards,

Ronald
Hardware: Raspberry Pi 3, OTGW, 433MHz Superheterodyne 3310 RF Link
Software: Ubuntu 16.04, Domoticz v3.5468, WiringPi, rc-switch

User avatar
ThinkPad
Posts: 1754
Joined: Tuesday 30 September 2014 8:49
Target OS: Linux
Domoticz version: beta
Location: The Netherlands
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by ThinkPad » Tuesday 26 January 2016 22:55

You bought the USR-TCP232-T module? I also have one of those, but didn't use it yet. The USR-TCP232-2 was self explaining, it just has a power jack so i could tap in my wires there.
Maybe read the datasheet to see if it clears things up for you.
ThinkTheme - theme for Domoticz
My (Dutch) blog: http://thinkpad.tweakblogs.net - My Domoticz scripts: Bitbucket
I'm not (very) active anymore on this forum as i don't use Domoticz anymore.

Draakje
Posts: 88
Joined: Thursday 22 October 2015 21:14
Target OS: Linux
Domoticz version: 3.5468
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by Draakje » Wednesday 27 January 2016 1:18

I bought something similar.. (although it does say USR TCP232 15/07)
No datasheet whatsoever....... Left clueless :P
Hardware: Raspberry Pi 3, OTGW, 433MHz Superheterodyne 3310 RF Link
Software: Ubuntu 16.04, Domoticz v3.5468, WiringPi, rc-switch

Skippiemanz
Posts: 283
Joined: Sunday 14 July 2013 20:21
Target OS: Raspberry Pi
Domoticz version: 3.5859
Location: Alkmaar, The Netherlands
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by Skippiemanz » Sunday 01 October 2017 21:11

ThinkPad wrote:
Tuesday 26 January 2016 22:55
You bought the USR-TCP232-T module? I also have one of those, but didn't use it yet. The USR-TCP232-2 was self explaining, it just has a power jack so i could tap in my wires there.
Maybe read the datasheet to see if it clears things up for you.
Proud owner of a otgw here and a USR-TCP23-T Could you point us in the right direction of connecting the USR-TCP232 to the otgw?

Thanks in advance!

Skippiemanz
Posts: 283
Joined: Sunday 14 July 2013 20:21
Target OS: Raspberry Pi
Domoticz version: 3.5859
Location: Alkmaar, The Netherlands
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by Skippiemanz » Thursday 26 October 2017 14:26

Skippiemanz wrote:
ThinkPad wrote:
Tuesday 26 January 2016 22:55
You bought the USR-TCP232-T module? I also have one of those, but didn't use it yet. The USR-TCP232-2 was self explaining, it just has a power jack so i could tap in my wires there.
Maybe read the datasheet to see if it clears things up for you.
Proud owner of a otgw here and a USR-TCP23-T Could you point us in the right direction of connecting the USR-TCP232 to the otgw?

Thanks in advance!
No one has an idea?

barbaar
Posts: 48
Joined: Wednesday 24 December 2014 17:01
Target OS: Raspberry Pi
Domoticz version:
Contact:

Re: Cheap ($11) RS232 to Ethernet converter on eBay

Post by barbaar » Monday 27 November 2017 11:26

So, I modified my OTGW and added a USR-TCP232-T2. On hardware level, all seems to be okay. But I think, I need to configure the USR-TCP232-T2. Reading the docs (http://www.usriot.com/products/ethernet-module/), it should be possible to do this over IP. The unit itself configures itself to 192.168.0.7:8234 and listens to 192.168.0.201.

On the usriot website are several tools available, and I can connect using a serial over IP connecting (using one of the tools provided). But I cannot find any config to adjust..

And ideas?

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest