To debug the new BIOS and FPGA tests, we had to develop another software module for the entire system — a simple software simulator of the target Alesta LX platform. This entire lengthy development cycle was necessary to ultimately streamline the entire process.

The initial task was to create embedded tests for FPGA debugging, which must run on the hardware platform itself. For these to work, in turn, we needed to write a new BIOS from scratch for about 90% of its code. This created a key problem: how to debug this very BIOS if the physical platform for testing was not yet available?

The decision was made to break this vicious cycle by creating an emulator — a software replacement for the hardware. The development process is now structured into a clear sequence:

1. The simulator itself is debugged on the main (host) platform. It is quite simple and has built-in debugging tools.
2. Using this functional simulator as a "test bench," the new BIOS is debugged.
3. Then, on the debugged BIOS, the tests for the target FPGA are verified and finalized.

This entire toolchain is first debugged and run in simulation. Only when all components work together correctly do we move on to testing on real hardware. From the outside, this may seem like a complex, multi-stage path, but in reality, it is the most efficient and reliable option possible.

The image below shows the Alesta LX simulator in operation during a debugging session. The next step will be the debugging of the new BIOS itself.

Happy upcoming New Year to everyone!