basejump_stl VS satcat5

BaseJump STL ( https://github.com/bespoke-silicon-group/basejump_stl ) has lots of these plumbing modules, silicon-validated several times

It depends on your mapping algorithm and whether the tools you’re looking at supported mixed-language synthesis, but you can always use our battle-tested components for these kind of functions: https://github.com/bespoke-silicon-group/basejump_stl

https://github.com/bespoke-silicon-group/basejump_stl maybe?

I needed 128-bit and 256-bit integers on an embedded project recently.

In short, it was for fixed-point digital signal processing. The raw input and output samples were int64_t. We needed to add, subtract, multiply, and accumulate these to do filtering and linear regression with no loss of precision.

Conventional bigintegers weren't an option because the target application doesn't allow heap allocation. So we rolled our own [1] stack-allocated, fixed-width big integer class.

[1] https://github.com/the-aerospace-corporation/satcat5/blob/ma...

And here's an open-source implementation I wrote a few years back. You can skip the part at the end that handles variable-length trailing bytes, since you have a fixed-width input.

My SatCat5 project also has a few options. Anything under src/vhdl/common/cfgbus_* can be connected to AXI or Wishbone with a simple adapter.

For an all-digital solution, here's an NCO that generates an arbitrary-frequency square wave from a numeric counter.