MiSTer FPGA Forum

robinsonb5 wrote: ↑Sun Feb 21, 2021 11:32 am I think I'd start with something simple - maybe take the MemTest core, learn to built it in Quartus, then figure out how to change the background colour and text colour. (My first project was on the Turbo Chameleon 64 cartridge - I took the hardware diagnostic core and used the graphics primitives and PS/2 mouse component to implement a simple "Pong" game.)

You're going to encounter both VHDL and Verilog - both languages have their pros and cons. VHDL will throw a compilation error for the tiniest of mistakes. Verilog will quite often march straight past the most blatantly wrong code and silently produce a non-working core as a result! For this reason, I tend to consider VHDL the better language for learning, at least until you have the base concepts secure.

The most important thing is to understand what type of logic is being described by your code, understand the difference between combinational logic and registers, and understand the difference between blocking and non-blocking assignments.

Would there be wider interest in some tutorials at some point?

dshadoff wrote: ↑Sun Mar 21, 2021 3:24 pm The first one is mostly a description of the language, without much information on how to put it to use.
The second one should be pretty good, but uses a Xilinx board (additional expense) and Xilinx software.

The skills are transferrable but may not be exactly one-for-one when transferring to DE10-Nano.
I think that author also had an Altera-focused book, maybe check to see if it’s still available.

• Computer Organization and Design: The Hardware/Software Interface; Patterson/Hennessy
• Digital Design; Mano/Ciletti
• Advanced Digital Design with the Verilog HDL; Ciletti

dshadoff wrote: ↑Sun Mar 21, 2021 5:08 pm Yes, this looks like the one I was referring to. It's a bit old - referring to DE1 and DE2 boards - but it's Altera- and Quartus-based.

Altera likes to push their "NIOS processor" which is effectively a CPU implemented in FPGA logic, as a means of performing sequential operations... They still do this, so those skills aren't out-of-date. However, you should know that MiSTer does not use NIOS, as the DE10-Nano includes its own ARM processor implemented in hardware. So don't get hung up on the NIOS-specific aspects. It might be useful on other FPGA boards at some other time, but not in MiSTer.

In general, when starting out, I would suggest that the major points of learning won't be Verilog versus VHDL - these are really just syntaxes - but rather, a method of thinking about how to design things in FPGA logic, using clocks, sequential logic, and combinational logic.

You will be getting a lot of feedback from the "compiler"/developer software, so it is important to become accustomed to one of them first (later, once understood, these are transferrable skills to other FPGA systems and development software as well).

Major aspects of the dev software you should get accustomed to are:
- The overall process of compilation
- why clocks are special
- how to prepare testbenches/simulations
- how to use the built-in logic analyzers (SignalTap on Altera chips)
- when and how to invoke specialized hardware (i.e. "megafunctions" on Altera)

Most beginner books don't spend even a moment introducing these concepts, which is why a proper course-like textbook is useful. Unfortunately, most are written for Xilinx FPGAs... and while the skills are transferrable, the boards they suggest to use are in the $300 range... plus the book itself.

Since you (probably) already have the DE10-Nano, you should start by looking at the documents supplied by the maker, such as "My First FPGA" and the "DE10-Nano User Manual" here:
https://www.terasic.com.tw/cgi-bin/page ... 6&PartNo=4

And just remember that we use version 17.0.x of Quartus for MiSTer cores, so get that version when you download Quartus.

jca wrote: ↑Sun Mar 21, 2021 8:00 pm Interesting Lecture:
https://opencores.org/usercontent/doc/1262707254

dshadoff wrote: ↑Sun Mar 21, 2021 5:08 pm Most beginner books don't spend even a moment introducing these concepts, which is why a proper course-like textbook is useful. Unfortunately, most are written for Xilinx FPGAs... and while the skills are transferrable, the boards they suggest to use are in the $300 range... plus the book itself.

dshadoff wrote: ↑Mon Mar 22, 2021 9:12 pm I wouldn't worry about the exact sizes.
There are a number of factors, including the fact that you are almost certainly using the Lite version whereas the official release usually comes from the Standard version of the tool.

As long as:
- you are using the official sources
- the compile is successful and
- timing issues aren't pointed out during compilation
...you should get the same results as the official core

Lightwave wrote: ↑Mon Mar 22, 2021 9:23 pm

dshadoff wrote: ↑Sun Mar 21, 2021 5:08 pm Most beginner books don't spend even a moment introducing these concepts, which is why a proper course-like textbook is useful. Unfortunately, most are written for Xilinx FPGAs... and while the skills are transferrable, the boards they suggest to use are in the $300 range... plus the book itself.

The strange thing is, we keep hearing that the DE-10 is targeted towards education (and is partially subsidized for that purpose), therefore you would think there would be a wealth of learning materials available for it if this is the case.

jca wrote: ↑Mon Mar 22, 2021 9:31 pm Previously I compiled some cores which worked but never paid attention to the size.
This time I wanted to be more meticulous and noticed the difference. The core seems to work properly so I was not really worried, just curious.
And yes I am using the Lite version.

dshadoff wrote: ↑Tue Mar 23, 2021 4:47 am There is an element of randomness required during the fitting operation, which could provide varied results.

bellwood420 wrote: ↑Tue Mar 23, 2021 5:17 amOf course the fitting operation requires randomness, but I don't think it's completely random. It is pseudo random.

Thanks all for this info! I am a software eng by trade, but I half got the MiSTer as a learning tool and half as an emulator box...

For those who are also just getting started, I found a series of more "MiSTer oriented" videos in the form of someone developing a core from scratch in a number of videos: https://www.youtube.com/watch?v=qxgM9NPrhqw

I don't want to put the cart before the horse, but I do want to get an okay grip on the fundamentals and then start looking at the framework. Is there documentation for the MiSTer framework living out there someplace that I can turn to as well?

Same here: software by profession, passionate with electronics (digital and RF). I never dared to look into FPGA until I found the site of Grant Searles and his multicomp project on a tiny FPGA board ($20-$30). After playing with it I realized that FPGA was not as hard as I thought but still not that easy. I looked for a developer board, had hard time deciding. When I found video on this MISTer project I decided to go with it: if I don't succeed learning FPGA I can put to good use.
In the end I decided that it was not such a good idea to learn as you not only have to learn HDL but also communication with the ARM. Result: it became a MISTer only device (no regrets) and I got myself a DE1, no longer available but I got a good deal on ebay. More than enough to learn: SRAM, SDRAM, FLASH, SD card, sound chip, switches and buttons, LEDs, 7-seg LED display, VGA, PS/2, Serial and still 2 40-pin connectors with a bunch of GPIO pins.
As for the framework: may be one day but at the moment I have chicken feet.

I'm using an Upduino v3.1 board for 30 bucks and following along with the Digikey videos which uses an IceStick.

Upduino board: https://www.tindie.com/products/tinyvis ... pga-board/
DigiKey Video Series: https://www.youtube.com/playlist?list=P ... NmQ_9CIKhb

The Upduino uses an opens source tool chain (Apio) and I'm on linux so its pretty simple to get going.

BUT and this is important- You have to breadboard, your own LEDS, buttons, 7 Segment Displays, etc. Basically a bit of Electronics background and Digital Logic. Like ohms law, how not to fry your LEDs, or your Board, etc.

The problem I've had so far is you have to learn how to use the internal 48Mhz clock. Otherwise you'll want to solder the two pins to allow the external 12 Mhz OSC to be used. Outside of that, SO FAR its all transferable to any Lattice iCE40 tutorials which Digikeys video series using the IceStick is one. Nandlands website mentioned above sells a board there and its also an iCE40 chipset so the tutorials should work with the Upduino. I'm gonna give that a try soon.

Also to get my feet wet with Verilog I used this website: https://www.asic-world.com/verilog/veritut.html

But Nandlands website again has an intro to Verilog. https://nandland.com/learn-verilog/

You really do have to wrap your head around the language which even though the Digi-key vids are great its going so fast I was missing stuff and reading helped.

The Upduino comes with roughly 5k LUTs so (if what I've heard is true) you could do a 6502 chip in it with tons of room to spare. So I'm thinking after I go through Digikeys videos and Nandland tutorials. I'm gonna try to do Mister Retro Wolf's video series also mentioned above on the Upduino and see if its possible. Probably more pain than its worth... but ya never know.

Well as Long as I don't get distracted. Its a lot to take in. But very interesting.