Electronic – pBlazSim Picoblaze simulator – Trouble Getting Started

Unfortunately, I do not think that the Picoblaze has hardware support for floating-point. If it does, you can do it in hardware. Otherwise, you will need to do it in software emulation mode.

Since I noticed that you asked the same question for both the Picoblaze and the Microblaze, maybe you need to ask yourself why you need to do floating-point operations.

In many cases, there are alternatives to floating-point operations. Fixed-point operations are a common alternative to floating point. You will need to study your algorithms to determine if it is possible to represent the values in a fixed-point math alternative to floating-point math.

For example, if you use an 4-bit fixed-point width, you can represent values in quantums of 0.125 between -1.0 to 0.875 with fixed-point representation. Larger values can be scalar multiples of these values.

Edit: Article explaining float-to-fixed-point conversion.

Here is a better way: Don't!

The best way to document the design is by using the original code (VHDL, or Verilog). This is the most accurate, and will always be up to date. For simple designs, schematics might be more readable but that is not true for medium to large FPGA designs. At that size, schematics become hard to follow, large, cumbersome, difficult to modify/update, and are impossible to debug. So just don't use them.

When I have to document an FPGA design with schematics, I do it with Visio and make it more of a high level block diagram than schematics. Doing anything with more detail is a frustrating and fruitless task.

I would also argue that VHDL/Verilog are not difficult to follow. If someone can't follow them then the problem is the person, not the code. I have some FPGA designs that if printed out would take up about 800 pages of standard paper. That same design, if shown using schematics, would require 2,000+ large pages. It is easier to get proficient at reading VHDL/Verilog than to transcribe 800 pages of VHDL code into schematics (and then keep it up to date and accurate).