QL on MIST FPGA board

[MIST]

I just released a new core incl. a "real" IPC based on the t48 core and the original firmware.

This allows to run games as keyrow scanning now works. And there's also audio. I'll upload another video once i find something interesting to show. Quill and the PD games i found aren't that entertaining ...

I still have a few small issues to fix. But my primary goal to get something close to the original machine has nearly been reached. If and how to continue from there also depends on you guys. I need at least a few motivated users to stay motivated myself ...

[Derek_Stewart]

Hi,

I have not used this type of system before, can different Cores be easily loaded?

How hard is the programming of the Cores?

I tend to have many different type of computers, this made satisfy my interest.

The wife would be happy not having lots of computers about the house...

[tofro]

Hi,

I have not used this type of system before, can different Cores be easily loaded?

Definitely. <F12> from the keyboard or a button press on the MiST front panel enter a menu system that allows selection of the cores on the SD card. A few seconds later you have an Amstrad CPC or Atari in front of you instead of the QL.

How hard is the programming of the Cores?

VHDL and Verilog are very C-like languages. So programming them as such is not really a big problem. What I find difficult is more - getting used to the mindset needed to program hardware instead of software - In software, everything is more or less sequential, in Hardware, a lot of stuff "happens at the same time".

Tobias

[MIST]

Yes, you need to get used to this kind if thinking. E.g. this code:

Code: Select all

  a <= 0;
  if ( a != 0) begin
     .... do something
  end

makes absolutely no sense to a normal programmer. In HDL this is a very common thing since the assignment (a <= 0) and the comparison (a != 0) happen at the same time. So if a at a given time isn't 0 it will be set to 0 and at the same time the "do something" is being processed,

But when rebuilding hardware it really makes things easier. E.g. if you need to run something in parallel (video and CPU for example) you just build two independent hardware parts inside the FPGA and they just each do their thing. Software based emulators usually have to interleave all kinds of processing to give the impression that things happen at the same time. In hardware they simply do ...

[MIST]

BTW: Joystick and the usualy PC key bindings (Backspace to ctrl-left etc) now also work. So i'd say i am 99% done with what i wanted to achieve. I will release the binary and the latest source code this evening.

Resource usage on the FPGA is 26% for logic and 6% for FPGA internal memory (the 8049 has its ram and rom inside the FPGA and also the extra line buffer for the VGA scan doubler are there) on the EP3C25 FPGA is use. So the smallest FPGA to hold this is something like the Altera EP3C10 which together with a small static RAM could be used to build a tiny QL replica.

This also means that the vast majority of the FPGA resources on the MIST board are still available. So the functionality of all those add-ons like graphics cards and the like could potentially still be added.

Another great possibility this kind of setup offers is its usage for rapid prototyping. Do you want to develop something like the zxpand? Just implement it inside the FPGA using e.g. an AVR core http://opencores.com/project,avr_core . And once you are satisfied you can start to build real hardware from this for use on real QLs. But you can do 99% of the hard- and software development before even touching a soldering iron.

[Derek_Stewart]

Hi,

I watched the QL video and the Amiga-Atari videos on You Tube.

The Mist board looks good, I would have save up for a board.

[XorA]

I guess the obvious question now is can it be upgraded to 68020 and support the extended screen modes from Q40/Q60 https://en.wikipedia.org/wiki/Q40_(motherboard) so that it can run smsq/e as well as classic QDOS?

I can't remember what network card was demoed at QLis30 but an emulation of one of those using the already described USB support work be cool as well.

[tofro]

I guess the obvious question now is can it be upgraded to 68020 and support the extended screen modes from Q40/Q60 https://en.wikipedia.org/wiki/Q40_(motherboard) so that it can run smsq/e as well as classic QDOS?

I can't remember what network card was demoed at QLis30 but an emulation of one of those using the already described USB support work be cool as well.

I'd rather not see a Q40/60 emulated for some reasons but instead a QL with SGC(-alike) and Aurora. This would keep the option to have a "switchable" upgrade path (by just ticking config boxes in menus) and both SMSQ/E and classic QL ROMS. One single implementation would be capable of having both a low end QL with only 128k and micro drive as well as a High-End 68020-based box with Hi-Res Multicolor Graphics.

68020, however, would be nice and desirable, and, judging from what has been implemented on the MiST for other platforms like Atari and Amiga, perfectly feasible.

Judging from the amount of people giving feedback here, I do, however not see a lot of interest...... (Please, guys, prove me wrong, even if it's summer holidays!!!)

Tobias

[vanpeebles]

I'd never heard of a MIST so I suppose some people might still be unsure as to what it actually is. etc. It does sound like a superb project though!

[Ralf R.]

It is great. My honest respect for such a thing. Yes, it would be very good to have Atari, QL and maybe also SMSQ/E on it. Even with Atari one can use SMS2. What a great idea.