rs232 and picoblaze :)

Hi all ! I bought a S3board from digilent. I ran some program to test it, included a serial parallel multiplier :) I'm currently thinking of a new project "just for fun". When I learned vhdl at university, we start a project by coding a very simple processor, who looks like a very simple picoblaze. Do you think if it's do-able to implement a pico blaze, plug it (internally in the fpga) with an uart and to run a kind of monitor ? For example with a 68K board, when from the console you can access to memory, dump or modify it, run some assembler command etc etc. I would like to run a kind of very simple SBC with this system. I read the documentation about picoblaze, but I'm afraid that the program must be written when compiling the vhdl ? Could we load the execution code, for example in the sram ? Thanks a lot, xavier.