Texture Copy

I have two textures
TextureA) 16x16 texture
TextureB) 512x512 texture
How do I copy TextureA to an area of TextureB.
CopyRect needs a source buffer and a Dest. buffer to work, and I don't see a function for working with 2 buffers.

Never mind I figured it out. For anyones information. The way to do it is as follows:

CopyRect 0,0,16,16,0,0,TextureBuffer(textureA),TextureBuffer(textureB)

Bye