Using C64 Core on MiniMig boards.

[alexh]

At this rate you'll have a release ready in no time ;-)

[Hojo Norem]

Impressive.  I await the day that I'll be able to run edge of disgrace on my Minimig.  (Actually could you test that?  I'm interested how well it could work cause it took me 2 weeks to get my C64 to play it all the way through without crashing or seriously glitching).

But out of curiosity, the game you tested were single load games.  It might be worth testing with some multiload games as well.  The loaders in some games can be quite forgiving while others are rather more strict (Creatures 2 comes to mind, the non cracked version that is)

[mikej]

"BTW: Above, you write ".bit file produced". Do you mean ".bin file" (as in, the file I can rename to minimig1.bin and boot up at the minimig) ?"

A .bit file is produced automatically - it contains a header with some extra info in. If you add the options to bitgen -Binary Yes (from memory so might be wrong) then the tool will produce a .bin file which is just the configuration data. That's what you need for the SD card.

There is something called a parallel cable 4 which runs a lot faster than the basic parallel configuration cable and is cheaper than the USB one - although not as fast. I found somebody making a clone of the Xilinx USB cable really cheap but I can't remember where I saw it. Probably in China.

/Mike

[boing4000]

@Hojo_Norem
edge of disgrace is certainly one of the very best C64 demo I've ever seen! I will try this as soon as I got it on real floppy disk.
May be the multiloader will fail as in "Deus ex machina" but a few hours ago I found the right timing setting. Now fpga64 shows a 49Hz 30.8KHz PAL screen! Its possible that now all loader will work, but I have to sleep a bit before testing (it's almost 01:00 o'clock in europe :-)).

@alexh
To release a binary or source, I have to remove the ROM images or replace its content with "$00" ro keep up existing copyrights. Currently the fpga core itself comprised the ROM images and I can not make this public, sorry.
To keep copyright up the core should load the image from sd-card, like minimig is doing. But this would require PIC reprogramming or some other solution.
If anyone has a better idea or request, please send PM to me!

[TheDaddy]

GOod job there!

Let us know when we can test it :-)

[Belial6]

"To release a binary or source, I have to remove the ROM images or replace its content with "$00" ro keep up existing copyrights."

How do VICE and FRODO legally release a rom?  I always assumed that they used a rom that was clean room cloned.  Could the ROM from one of those be used?

[Hojo Norem]

May be the multiloader will fail as in "Deus ex machina" but a few hours ago I found the right timing setting. Now fpga64 shows a 49Hz 30.8KHz PAL screen!

49Hz sounds a little slow.  I thought the PAL C64 refreshed at 50.12Hz? (I know this because when recording my Panasonic DVD-recorder skips a frame now and again and my Sharp DVD-recorder makes the audio go out of sync with the video).

[boing4000]

Hojo_Norem wrote:
49Hz sounds a little slow.  I thought the PAL C64 refreshed at 50.12Hz?

Yep it should be at least 50Hz @ 30-31KHz but the timing settings are a bit difficult to adjust. First it was 56Hz and everything was running too fast. Perhaps I may be able to create a 2nd dcm clock generator to gain a better adjustment.

Until now also PAL and NTSC 15KHz screen is available. Currently just static but also in the future selectable via existing 15/31KHz jumper. Im working on it...

I found out that multiloader are very sensible programming stuff. Right now no scene demo is able to load the next part. It may caused by the core (source) itself but I can not reproduce that theory. If possible someone else could test the following demos on another FPGA64 porting:
- Deus Ex - Machina
- Oxyron - Natural Wonders
- Execute - Overdrive

@Belial6
I will inform me about that issue. If there are public/free ROM image available, I could implement them in the core. But first I'll have to make sure.

Thx :-)

[denli]

Belial6 wrote:
How do VICE and FRODO legally release a rom?  I always assumed that they used a rom that was clean room cloned.  Could the ROM from one of those be used?

For FRODO:
http://lachner-net.de/index.php?option=com_content&task=view&id=3&Itemid=5

The emulator needs also C64 ROM files. For copyright reasons this [sic] files are not included in the ipk package. This files can, for example, copied from a original C64. After Frodo is installed [...], this [sic] files must be copied to "/opt/QtPalmtop/bin/frodo". The following files are needed:

Kernal ROM
Basic ROM
Char ROM
1541 ROM

This page contains some links for the C64 that might be of interest (including the original manual).
http://frodo.cebix.net/

[Palm]

If you want testers, and don't want to distribute your core as it is (containing embedded roms) .. how about we email you a copy of our roms, so you see we have them, then you make the core available to us (email back?) after we have acknowledged having roms beforehand.

I know this is totally silly, as probably everyone can DL them illegally from the net, but still -- it would provide a way to do it....somehow.

BTW: It would be cool if there were some kind of dram or other storage device on the minimig (apart from SD card) which enabled core to easily load data from it. Then we could have filled this space-area/chip (whatever) with e.g. rom files for the core to load upon boot.

Is itpossible to add a memorychip to any existing lines so we can connect dram or flash or something ? I think the next gen of minimig should have a easy flashable chip in which we can stuff with romsfiles. That would make core-sharing so much easier when they could be shared without pre-compiled romdata.

Any opinions on this ?

[Speelgoedmannetje]

denli wrote:

Belial6 wrote:
How do VICE and FRODO legally release a rom?  I always assumed that they used a rom that was clean room cloned.  Could the ROM from one of those be used?

For FRODO:
http://lachner-net.de/index.php?option=com_content&task=view&id=3&Itemid=5

The emulator needs also C64 ROM files. For copyright reasons this [sic] files are not included in the ipk package. This files can, for example, copied from a original C64. After Frodo is installed [...], this [sic] files must be copied to "/opt/QtPalmtop/bin/frodo". The following files are needed:

Kernal ROM
Basic ROM
Char ROM
1541 ROM

This page contains some links for the C64 that might be of interest (including the original manual).
http://frodo.cebix.net/

:-?
AFAIK when I downloaded VICE from their main site it worked out of the box. And I vaguely remember something of certain Commodore 64 software being legally freely available.

[Palm]

Dude, same here. I downloaded vice(x64?) for OSX and it too worked out of the box.

Espen

[boing4000]

I dont know the full rights-system of emulators including rom images on the internet. But if one will share this files without permission it could cost a huge amount of money. Even if this rom copyrights are very old like the C64 one.

The idea of having some kind of flashrom to store necessary rom images is a good one! Using PIC to upload (different) rom files in the current state, will require an intelligence how to handle Amiga-kick.rom and anything-else.rom to the just uploaded core file.
Handshaking is a difficult thing to do, especially in complex (working) core files like a native C64 that dont have any clue of SPI bus system or "whats a PIC...?".

Perhaps in the future it will be possible, but it would require a lot of work and knowledge about the ported system structure. Still it is possible, like we see on Minimig Amiga Chipset and its PIC communication (floppy simmulation) :-)

[alexh]

Is there a hard reset on MiniMig PCB? Could you program the FPGA with a core which will transfer a file from SD CARD to the SRAM using the standard PIC and then reprogram the FPGA with your core? The SRAM should hold it's contents.

[boing4000]

That could indeed be a way. The s-ram will hold its data even while hard resetting or reprogramming the FPGA.
We would use the working minimig Amiga chipset core to fill a special part of s-ram with some rom image. Then simply swap sd-card, reset the system by pgm reset button and let PIC upload the next core. If this core will look for its rom data in the same address range uploaded before, then it could actually work!

In this case no PIC reflashing will be necessary! I can try to check this out by some test-core that only read particular add.ranges filled by the "Amiga" core.
Thx for this idea :-)

[Palm]

I was wondering, are the sources for the c64 core free so that I can download them, embed my own ROMs from my C64 into the source, compile to a single .bin file so that I can use this ?

It would require ppl to install ISE and compile themselves, but after reading you tutorial, it looks very easy to do.
(downloading SP4 IDE webpack now -- soon trying to compile the minimig sources..ehhe)

Espen