Honeywell Rth8500

I live in a condo and have two Honeywell T6069 in my unit. I bought two Honeywell programmable RTH8500 to replace the two units, but have run into a wiring problem.

The son is connected to the old thermostat with color codes - no letters. The ONLY RTH8500 uses letters (as I suppose you can not rely on the color of the son for the installation).

The T6069 is connected like this:

The fan motor:
- Brown = High
- Blue = Average
- Red = low

Other:
- Valve = yellow (cool)
- Valve = Orange (heat)
- Black = L1
- White (not connected to the T6069).

The question is basically what I know son that correspond to in terms of funtion, but these functions are not labeled on the new thermostat, there are only letters.

Now, the old thermostat does not require power, as far as I can see, but the new one does. Thus, the son would be black and white power.

I tried looking online, but there is no place where I can find information on exactly what the letters can be in terms of function.

Does anyone know what the letters represent? For example, what letters would be the fan motor? And who would valve, for a (three steps?) Heat pump?

R-24V common
w-heat
Y-cooling
g-fan
b-shock heat
o-shock cooling
heat stage w1-1
Heat second-stage W2
y1 first-stage cooling
Second-stage cooling y2
rh-car heat
rc on self-cooling