should i install cuda sdk for write opencl code?

Hi, i want to write OpenCL code run on both 9600GT/AMD240,
but i can’t find a nvidia opencl sdk, what should be installed?
thanks in advance!

Refer this
http://wiki.tiker.net/PyOpenCL/Installation/Windows?action=AttachFile&do=get&target=OpenCL+and+PyOpenCL+installation+manual.pdf

https://developer.nvidia.com/opencl