artfullpac

I am an engineering student and I'm new to the Honeywell HC900 system. I have an assignment to create adaptive control with a reference model and then test it on a laboratory model. I have a few questions regarding this subject.
1. Is it possible to change the cycle rate in HC900? I am aware of the normal and fast scans but could I put a custom cycle rate?
2.Could someone explain me the execution order and the cycle rate. (Does it mean if I have, for example, a cycle rate of 1 second and 2 function blocks, that after 0.5 sec block with execution order 1 will have calculated values on output and after 1 sec second block will have output too or at the end of cycle time the output is put at the same time on both blocks?)
3.How do I write the transfer function which I need for the reference model in Hybrid Control Designer? (I have some ideas with sumator blocks, but I need a better understanding of the above mentioned question, taking into account me needing outputs in steps y(k), y(k-1)..... )
4.Is it possible to write a recursive algorithm based on a vector of previous values? (to allocate some space in memory for writing previous values and calculate new ones for parameter identification (to mention a few examples)).
5.Is HC900 a PLC or is it a hybrid controller? What is the difference?
6.Are there any lessons or tutorials for hc900 available for download? Why is there almost nothing about this controller?(nobody uses it or what?)
THX!