Author
| OCM hardware configuration
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NYYRIKKI
msx master
Posts: 1474 |  Posted: March 18 2008, 21:53 |
I hope that I soon get OCM, but at the moment I'm a bit puzzled...
- What different hardware configurations are available at the moment?
- What you think is the best (MSX) hardware for OCM at the moment?
- Can someone tell in English what are the major differences? Chips included etc.
- How safe it is to change hardware? How likely it is to burn the Altera chip?
- Are there different programs for changeing the hardware?
- Can you freely upgrade and downgrade between hardware versions?
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NYYRIKKI
msx master
Posts: 1474 | Posted: March 27 2008, 22:06 |
UP!
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Sonic_aka_T
msx guru
Posts: 2257 | Posted: March 28 2008, 01:25 |
Quote:
| - What different hardware configurations are available at the moment?
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Sofar I've seen two releases on MRC, but I'm sure there are more. These are mainly mods of the original MSXA distro.
Quote:
| - What you think is the best (MSX) hardware for OCM at the moment?
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If you're talking about the soft-hardware, then I suppose they're all more or less the same. There's no mod which gives you a MoonSound or GFX9000 if that's what you mean.
Quote:
| - Can someone tell in English what are the major differences? Chips included etc.
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Like said, all are minor mods (improvements) of the original code. I haven't heard of any new chips being emulated.
Quote:
| - How safe it is to change hardware? How likely it is to burn the Altera chip?
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I shouldn't burn anything, but you may end up bricking the darn thing. In that case you'll need a cable to rewrite the FPGA.
Quote:
| - Are there different programs for changeing the hardware?
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I think so, but it already ships with Quartus.
Quote:
| - Can you freely upgrade and downgrade between hardware versions?
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Normally, yes, unless something goes wrong and ends up bricking your OCM. |
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spl
msx professional
Posts: 714 | Posted: March 28 2008, 17:17 |
NYYRIKKI
See all the documentation about the unnoficial but major improvements of the 1chipMSX code here:
http://www.webalice.it/gnogni/
Doc is included in the zip file. Many important problems have been now solved.
Regards, |
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NYYRIKKI
msx master
Posts: 1474 | Posted: March 28 2008, 21:51 |
Ok, thanks for the info...
It just seems that more I try to understand of OCM the more questions I get...
One thing that really puzzles me is that MSX-BIOS is not delivered on CD with the device
I can also read rumours about SYSTEM.HEX file that can be put to SD-card, but I can't find any information about the file structure.
It would be also nice to know how the original BIOS has been put in to the flash...
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Edwin
msx professional
Posts: 589 | Posted: March 28 2008, 23:07 |
The .hex file is actually rather simple. It's an intel something hex format. You can find a description of it on the net. But you can basically create those with Quartus as well if you want to try and change the roms.
Supposedly you can place a 256K rom file as the first file on the SD card and it will read that instead of the one in the flash rom. I never got it to work properly, but you can check here for more info. |
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NYYRIKKI
msx master
Posts: 1474 | Posted: March 29 2008, 08:03 |
Ah, finally a link that has good information in English! Thank you, this is what I needed!
Now I actually think that the ROM's need to be in SD-card in binary format, not HEX-format... not sure though... have to try today...
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NYYRIKKI
msx master
Posts: 1474 | Posted: March 29 2008, 10:14 |
Yes, I used hex2bin, modifyed the ROM and put it to MMC. Works like charm  |
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NYYRIKKI
msx master
Posts: 1474 | Posted: March 29 2008, 12:09 |
WTF I just realized that they have used 128KB for KANJI-ROM, but there is no KANJI-BIOS present at all ... and this device has >20MB of totally unused memory... weird... really weird...
Someone with more knowledge, would it be hard or "expencive" to assign RAM from 06C0000-06DFFFF to slots 0-1 and 0-3 as ROM?
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Alex
msx lover
Posts: 87 | Posted: March 30 2008, 23:01 |
Don't know how easy/hard it is to use the extra RAM.
As far as I know, the device contains 32MB RAM because of cost/availability reason; smaller RAM chips are more expensive because they get produced/sold less (if they still get produced at all...)
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NYYRIKKI
msx master
Posts: 1474 | Posted: March 31 2008, 00:09 |
Actually this is now already implemented by HRA. I think he does not sleep at all 
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Alex
msx lover
Posts: 87 | Posted: April 01 2008, 21:37 |
I should contact him some day. I have some enhancements in mind that I want to start working on but I don't want too many branches to come into existence.
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