Rather than reading tutorials and then creating the project according to what I learned, this time I started out with the project defining what I need to learn. One does have to eventually step away from what others teach and think for one's self. It is empowering.
I decided to begin with the P1V verilog project and to attempt to replace the CPUs with an optimized Forth CPU. It seemed that Zen Forth and the eP16 were the best available, but it is all in VHDL and on a Lattice FPGA. So I am learning both Verilog and VHDL in parallel.
More specifically, I have actually decide to learn both Altera with Quartus II and Lattice with Diamond IDE, and Verilog and VHDL at the same it. This is not going to happen quickly (like in a weekend), but slogging along over the long haul has its rewards.
So far, I have got the P1V loaded and working on the BeMicroCV with Tachyon Forth or pfth Forth, so I have demonstated that the Verilog code works and I can opereate Quartus II V.15.0.2.xxx. And determined how to make modifications to the BeMicroCV and CVA9 that will enhance their usefulness
Verilog looks easier to learn, but I haven't gotten deeply into the P1V quite yet. I switched over to the eP16 code at this point. Zen Forth has long been something I wanted to get into. So I am now trying to get the Lattice Brevia2 XP2 loaded. And C. H. Ting's documents seem to demand I learn something about it along the way. It also may help me to eventually understand the P1V Verilog as that code stands alone without a lengthy presentation.
Now I am reading the eP16 documentation with intentions of getting the ZenForth working on a Lattice Brevia2 XP2 that I already purchased. The documentation from C.H.Ting is clear and very informative. I also have a VHDL Tutorial which includes a conventional 32bit CPU example.
I also have a PDF that compares Verilog and VHDL with examples. I keep returning to that to see what might be confusing me. So far, it seems to be very rewarding -- especially contrasting Verilog and VHDL. I must have learned something from Parallax over the years as it seems to be easier than I expected.
There are code converters - VHDL to Verilog, and Verilog to VHDL. I suspect the VHDL to Verilog direction might be safer to purse. But I can't see exploring these until I at least attempt to visualize do the changeover without automation.
And I am really enjoying what FPGA bring to the situation. I can have anything I want (within reason). I don't have to wait for the Propeller II to have more resources. And I don't have to look at a minefield of specifications for switching to another brand that may or may not be what I want.
In fact, I am beginning to think that learning Verilog and VHDL in parallel might be a better way to go.
Hwang Xian Shen, Puddleby-on-the-Marsh.
All things considered, I can live and thrive without Microsoft products. LINUX is just fine.