only two

[pramodsinha]

Dear all,
How is it possible to communicate with two pics connected with two wires only. Means power and communication signals both should be provided by these two wire only.
If some tips or schematic will be provided it will be highly appeciable. Thanx to everybody.

[BobK]

Hello Pramodsinha,

Follow this link to an explanation and schematic from Ms. Melanie. I haven't gotten around to trying it myself but its on my list of things to try someday.

http://www.picbasic.co.uk/forum/showthread.php?t=1761

Do a search for Data + Power and you should find one or two more examples/

Happy Holidays!

BobK

[rmteo]

The solution in the thread you linked to looks like it can only supply a small current to the slave (I'm guessing in the order of less than a few mA) - correct me if I am wrong. If the slave has to drive some outputs (say a motor or a lamp), do you know of a way that will allow the slave to drive a load of say 1A or more?

[mackrackit]

Do a search for DCC. There was some talk about this a while back. Someone was doing a similar app with truck and trailer wiring, but I can not find it now.

[rmteo]

Thanks, Dave. I'm familiar with the workings of Digital Command & Control - checking to see if there is anything else out there.

[BobK]

Hi rmteo,

The request was for communications between 2 PICs over 2 wires. Not to supply current to drive a motor or lamp remotely. If you want that then you could control a remote power source or should consider something along the lines of X-10. There you can run a 12/2 or 14/2 110VAC cable and use the X-10 commands to turn lights or motors on and off without the use of PICs. I am in the alarm business. We have several alarm device manufacturers that have devices that have both power and communication over two wires but none of the devices actually draw more than a few ma's of current. The other option is RF controlled devices.

BobK

[Charles Linquis]

You need to use a drive using a voltage regulator. I believe Melanie has posted a method. Look for that.

[rmteo]

Hi rmteo,

The request was for communications between 2 PICs over 2 wires. Not to supply current to drive a motor or lamp remotely. If you want that then you could control a remote power source or should consider something along the lines of X-10. There you can run a 12/2 or 14/2 110VAC cable and use the X-10 commands to turn lights or motors on and off without the use of PICs. I am in the alarm business. We have several alarm device manufacturers that have devices that have both power and communication over two wires but none of the devices actually draw more than a few ma's of current. The other option is RF controlled devices.

BobK

Thanks. As Dave mentioned and I replied, DCC does it and I am familiar with the technique.

[pramodsinha]

Thanx for the support got from diffrent sources i have to send data only so i need only very small curent. But still i need more illumination on my quirry to start my R&D work but still this is highly appreciable.

[sougata]

Dear All,

I know to some extent the solution Pramod is looking for. He needs a multi-master multi-slave RS485 multi-drop network of <b>sensors</b> wired over a distance of more than 1500 meters. The total number of sensors could be upto 255. More of like a CAN.

PS. Dave were you mentioning this thread : http://www.picbasic.co.uk/forum/showthread.php?t=9406

[pramodsinha]

Dear Sogata,
I am looking for the solution exactly what you have mentioned. But i think can has limitations of the distance.
thanx

[mackrackit]

PS. Dave were you mentioning this thread : http://www.picbasic.co.uk/forum/showthread.php?t=9406

That is it!!!
Thanks.