X10 Community Forum

🔌General Home Automation => Automating Your House => User Modified Devices => Topic started by: russellc on December 06, 2012, 06:38:03 PM

Title: CM19A internals
Post by: russellc on December 06, 2012, 06:38:03 PM
Hi, I'm an Australian and would like to be able to receive RF codes from my DS12 units dotted about the house, but it's now almost impossible to find the CM19E 433Mhz version.  Not to mention the ludicrous difference in pricing between the US and here for X10 parts.

I was wondering whether anyone in here has opened up a CM19A and can tell me whether it uses a daughterboard for the RF side of things, or whether the RF bits are heavily integrated with the other parts.

Obviously, if I can change a CM19A to a CM19E by just changing the RF bits (and I already have a couple of receivers), that'll be a win to me.

Title: Re: CM19A internals
Post by: russellc on December 06, 2012, 06:59:10 PM
Well, I just found a site with some internal pictures of a CM19A, and it's not good news for me. 


Looks like it's back to the drawingboard of trying to receive the RF with an RF module and my arduino.    >*< 

Pity that the DS12A protocol seems to be a closely guarded secret.

Title: Re: CM19A internals
Post by: dhouston on December 06, 2012, 07:43:39 PM
The X10 RF protocol is documented here...
The DS12A only sends two codes which are easy enough to capture.
The security devices also send a code to indicate a low battery but I never investigated that. Charles Sullivan may have documented it and someone here may have a link.

There's some PicBasicPro code here...
which you might be able to adapt for the Arduino.
Title: Re: CM19A internals
Post by: Brian H on December 07, 2012, 06:11:30 AM
If you are trying to use the CM19A and DS12A US and Canadian versions.
They are 310 MHz RF frequency models. As you indicated.

The external and internal photos. Along with the schematic of the CM19A.
Are on the FCC Database web page. In the details tab.
Grantee: B4S
Product Code:CM19A


The DS12A.
Grantee: B4S
Product Code: -DS11A  {Yes that is the ID used for both the Radio Shack version and the DS12A X10 Version of the sensor}