Can I control the size of sampleFrames in my VST effect?

[panu]

This has probably been discussed in the past, but I couldn't find anything useful through the search. I'm developing a VST plugin that will eventually be adapted to run on a hardware DSP processor. I would like to be make the block size close to very small (16-64). Can I directly control the size of sampleFrames somewhere? The host I'm using is Cubase LE.

Thanks.