Hi Harry:
jcgalvezv, this comment re the TM751 is intriguing. If I understand correctly, you want to open a TM751, and use the daughterboard along with the Firecracker as an RF link. You're not really intending to use X-10 at all?
No, I want to have a completely wireless X10 system. Firecracker to send commands and TM751 daughter board to receive commands sent from all the motion sensors and remote controls directly to the microcontroller. TM751 daughter board has the capability to receive commands from all the house codes.
Juan C.