Arduino based Oregon Scientific sensor

Hi there,

I'm new here and want to start a new Arduino project: make a Oregon Scientific sensor clone. What I want to do is to measure room relative humidity & temperature as well as my wall temperature. The whole point is to give me the relative humidity of the air at the temperature of the wall to see if I can expect condensation there and therefore mould.

As a first step, I would like to send data to the my weather station using their protocol.

I purchased a 433Mhz transmitter from eBay:

and found the specification of the Oregon Scientific protocol here

I found a guy who managed to transmit Oregon Scientific data to the weather station but he wrote the whole thing in ASM, which is a little too hardcore for me to understand.

From what I understand, I will have to re-write a part of the transmitter library before starting any other development. Does anyone have such an experience to point me in the right direction?

Thanks ! Martin