Power line comms X-10

[versatronics]

Hi
I did a search on the forum on power line and mains communications but never turned up anything. I see PBPro has commands for X-10. Does anyone know if any cct ideas or suggested chipset were ever published here to help get me started.
I want to monitor my geyser for a few months to 'learn' its habits and then control it remotely for an optimum efficiency. I also want to turn a few night lights on and off at dark time.
regards
Graham

[dhouston]

The PBP commands are for use with a TW523 or equivalent. They are rather limiting with no support for the newer extended commands.

Anand Dhuru has posted here a few times about designing his own send/receive circuits (for 230V). And there was an exchange between Anand and Darrell Taylor about modifying the X10 Out command for direct output of 120kHz bursts, eliminating the need for a TW523.

There was a recent thread where I listed a few powerline modem chips which might be applicable (although most now available are FSK) and Anand referred to a Nuts & Volts article (Building the X-Lock) from September 2001 that has a schematic for a two-way interface using simple components.

[versatronics]

Hi Dave
I could not find any of these articles, also I do not get nusts and volts in SA.
I have been googling for chipsets and came across the TDA 5051 which looked promising, but once again was not avaialble here in SA. Looks like I will have to design and build the modem myself from discrete bits!
Graham

[dhouston]

I found all of the threads in a flash by searching on "Anand Dhuru". Here are the ones of most interest.

• http://www.picbasic.co.uk/forum/showthread.php?t=3057
  http://www.picbasic.co.uk/forum/showthread.php?t=7115
  http://www.picbasic.co.uk/forum/showthread.php?t=1696

You can buy back issues of Nuts & Volts from their website. Anand attached a schematic, scanned from the article, to a message in one of the above threads.

[Darrel Taylor]

Might also be of use.
http://www.picbasic.co.uk/forum/showthread.php?p=34854

[dhouston]

Might also be of use.

Perhaps, but probably not in the case of Status Request. There are only a few X-10 modules that respond to Status Request and those do not actually reflect the state of the load - merely the state of the module. The lamp might be burned out, turned off at its switch or unplugged but the module will still report its ON if that's the state of the module. It's more a, "What's your best guess of status?" request and a, "Your guess is as good as mine." response.

BTW, the reason meL supports the BasicStamp codes is that Xout (and Xin) were original BasicStamp procedures. The non-Pro PB syntax is based on PBasic.