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Re: MSX2 Compatible Computer Project [message #7276 is a reply to message #7263] Tue, 17 March 2020 12:54 Go to previous messageGo to next message
tangent is currently offline  tangent
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Sergey wrote on Mon, 16 March 2020 12:01
I am wondering if any of these cartridges require +/-12V? Another simple thing to try is replacing the power supply, check if you have 5V/3A or so power supply around that you can use.
Unfortunately I didn't notice an improvement using a 5V/3A power supply. I think the only cartridge I have which requires +/-12V is an ASCII MSX-Serial 232 which seems to be working perfectly. Smile

jordi.solis wrote on Mon, 16 March 2020 15:36
If someone knows in which area of ​​the BIOS the character map is located, I will try to make an msx2 + BIOS with PAL character map.
I'd be very interested in this!
Re: MSX2 Compatible Computer Project [message #7285 is a reply to message #7276] Tue, 17 March 2020 23:44 Go to previous messageGo to next message
lintweaker is currently offline  lintweaker
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tangent wrote on Tue, 17 March 2020 20:54
Sergey wrote on Mon, 16 March 2020 12:01
I am wondering if any of these cartridges require +/-12V? Another simple thing to try is replacing the power supply, check if you have 5V/3A or so power supply around that you can use.
Unfortunately I didn't notice an improvement using a 5V/3A power supply. I think the only cartridge I have which requires +/-12V is an ASCII MSX-Serial 232 which seems to be working perfectly. Smile

jordi.solis wrote on Mon, 16 March 2020 15:36
If someone knows in which area of ​​the BIOS the character map is located, I will try to make an msx2 + BIOS with PAL character map.
I'd be very interested in this!
There is no such thing as a 'PAL' character map Razz . Unfortunately the supported character map is hard baked into the BIOS so changing the language bits does not help.
Potential keyboard layouts:
       KEYTYP  keyboard layout
               0 = Japanese 
               1 = International (QWERTY/other) 
               2 = French (AZERTY) 
               3 = English 
               4 = German (DIN)
               5 = USSR
               6 = Spanish
               7 = Swedish ??
What version do you need? Most variants are available on the net.
Re: MSX2 Compatible Computer Project [message #7291 is a reply to message #7285] Wed, 18 March 2020 10:32 Go to previous messageGo to next message
jordi.solis is currently offline  jordi.solis
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Hi Guys,
Maybe the default chartset map differs from NTSC to PAL BIOS
What refers to my preferences, the only thing that I want is fitting the current omega keyboard with it's keycaps, let me explain:
with the NTSC BIOS version, when I push on 2@ key I obtain the number 2 or " simbol, but with the PAL version of the BIOS all keycaps fit with their symbols.
So that, I will try with international or english, and if I get an spanish set of keycaps maybe that.

kind regards.
Re: MSX2 Compatible Computer Project [message #7294 is a reply to message #7291] Wed, 18 March 2020 11:55 Go to previous messageGo to next message
jordi.solis is currently offline  jordi.solis
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Hi Sergey,

If bit 0-3 on byte #002C sets the keyboard language... What does it do the JP2 jumper?

Let me know
Re: MSX2 Compatible Computer Project [message #7295 is a reply to message #7294] Wed, 18 March 2020 11:59 Go to previous messageGo to next message
Sergey is currently offline  Sergey
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jordi.solis wrote on Wed, 18 March 2020 11:55
If bit 0-3 on byte #002C sets the keyboard language... What does it do the JP2 jumper?
It selects the Japanese keyboard type/layout. It is MSX specs, so I thought I should implement that. Probably it is useless for European/US layouts Smile
Re: MSX2 Compatible Computer Project [message #7299 is a reply to message #7295] Fri, 20 March 2020 08:18 Go to previous messageGo to next message
jordi.solis is currently offline  jordi.solis
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Hi Guys, thanks for helping me

I tried changing the contents of 2c memory and that is what I fount:
both, MSX2 and MSX2+ NTSC BIOS had 00 on that memory location (corresponding to Japanese?Wink and this does not match with my keyboard at all, MSX2 PAL BIOS had 11 on that memory possition (what would mean qwerty international) and this works pretty good to me.
the better I would dream would be Spanish layout working but I'm not sure if possible without rebuilding the entire keyboard PCB because the shape of some keys (like ENTER key) are different but I would like to try and found what can and cannot be done.

So, I tested changing this byte on my BIOS but nothing happened. Neither with Japanese jumper.

"There is no such thing as a 'PAL' character map Razz . Unfortunately the supported character map is hard baked into the BIOS so changing the language bits does not help."
That makes sense to my tests.

"What version do you need? Most variants are available on the net."

I would be happy if someone helpme to have any of those versions, international, Spanish and maybe some other like English.

Kind regards.
Re: MSX2 Compatible Computer Project [message #7300 is a reply to message #7299] Fri, 20 March 2020 10:25 Go to previous messageGo to next message
Sergey is currently offline  Sergey
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Hi Jordi,

You can try using an MSX2 BIOS from an MSX2 machine of your choice on Omega.
Preferably, the slot mapping should match that of Omega. But if needed, it is possible to modify the expanded slot mapping by reprogramming the respective SPLD.
If in doubt you can test the BIOS in OpenMSX using a custom machine configuration.

Thanks,
Sergey
Re: MSX2 Compatible Computer Project [message #7306 is a reply to message #4137] Sat, 21 March 2020 04:58 Go to previous messageGo to next message
lintweaker is currently offline  lintweaker
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Hi,
With this link you should be able to find 'systemroms.zip' which holds the roms for a lot of MSX machines.
http://www.msxarchive.nl/pub/msx/emulator/openMSX/

Wrt slot order, I have found that the MSX(2/2+) BIOS is not that picky where it subroms are. It just looks from roms with start with 43h, 44h (normal program ROMs use 41/42h).
On my homemade MSX (Z8TY) I have expanded slot 0 and most ROMS live in a slot 0 subslot, works just fine.

I think the same goes for RAM, it should not matter in what slot the RAM lives (maybe RAM in slot 0 subslots would not work). (otherwise e.g. RAM cartridges would not work)
Re: MSX2 Compatible Computer Project [message #7311 is a reply to message #7306] Sat, 21 March 2020 14:37 Go to previous messageGo to next message
bifo is currently offline  bifo
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lintweaker wrote on Sat, 21 March 2020 04:58
Hi,
With this link you should be able to find 'systemroms.zip' which holds the roms for a lot of MSX machines.
http://www.msxarchive.nl/pub/msx/emulator/openMSX/

Wrt slot order, I have found that the MSX(2/2+) BIOS is not that picky where it subroms are. It just looks from roms with start with 43h, 44h (normal program ROMs use 41/42h).
On my homemade MSX (Z8TY) I have expanded slot 0 and most ROMS live in a slot 0 subslot, works just fine.

I think the same goes for RAM, it should not matter in what slot the RAM lives (maybe RAM in slot 0 subslots would not work). (otherwise e.g. RAM cartridges would not work)
the problem isn't going to be 'can we make the thing function' it's going to be 'can we build a machine that msx hardware sees as being msx.

my project slowed down because i purchased an old korean MSX2, 128k/128k, and it works fine for me to test software on. the memory structure is completely different. the MSX standard was brilliant in the time. that being said, the question is how flexible is the standard when we're bodging together a computer designed by a brilliant nerd on his down time.

i mean, when wozniak was selling kits for the apple 1, how many were successfully built into machines you'd pay $10k for

[Updated on: Sat, 21 March 2020 14:38]

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Re: MSX2 Compatible Computer Project [message #7316 is a reply to message #7311] Sat, 21 March 2020 22:50 Go to previous messageGo to next message
Sergey is currently offline  Sergey
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Hi,

So I figured why MSX2+ BIOS was not booting with the logo... It was a rather silly mistake in the Slot Select SPLD (omega-slot_select.pld).
Initially I programmed the SPLD so that only 16 KiB of Flash ROM are mapped to slot 3-0 0x0000-0x3FFF. Obviously, MSX2+ uses Kanji BASIC ROM to show the boot splash screen. It is located in slot 3-0 0x4000-0xBFFF. I did modify the SPLD to map that area to Flash ROM, but I neglected to modify the ROM address A16 logic...

Anyways, I've fixed the issue and posted the updated SPLD code on the GitHub.
I've also updated the make_rom.sh to create ROMs for MSX2+.

--Sergey
Re: MSX2 Compatible Computer Project [message #7319 is a reply to message #7316] Sun, 22 March 2020 12:53 Go to previous messageGo to next message
jordi.solis is currently offline  jordi.solis
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Hello people,
Someone very kind has sent me the corrected NTSC-BIOS files for the international keyboard.
His name is Petr Ŝvejk. Thanks from here.
My omega already works as an MSX2 +, it shows the logo and has the keyboard that corresponds to the characters you type.

I attach the file here temporally. https://drive.google.com/open?id=1heawxaSLOMHRaK2SyI1P-lILd5IxHykw

Kind Regards
J. S.
www.msxmakers.com
https://i.imgur.com/pOWR5wc.jpg
Re: MSX2 Compatible Computer Project [message #7327 is a reply to message #7319] Tue, 24 March 2020 12:21 Go to previous messageGo to next message
jordi.solis is currently offline  jordi.solis
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Guys,
Maybe someone here would be interested on this thread.

https://www.msx.org/forum/msx-talk/hardware/msx-usb?page=0

Regards.

J. S.
http://www.msxmakers.com
Re: MSX2 Compatible Computer Project [message #7329 is a reply to message #7327] Wed, 25 March 2020 23:48 Go to previous messageGo to next message
Sergey is currently offline  Sergey
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Hi,

Using the BIOS image provided by Petr/Jordi, I've created a patch to update the keyboard layout of Japanese MSX2/MSX2+ BIOSes to international keyboard layout. The patch and the updated make_roms.sh script are available on project's GitHub. The script now also generates an MSX2/MSX2+ ROM image (omega_msx2_msx2+_ntsc.bin).

On my machine, I've connected an external switch to the JP1 header, so that I can switch between MSX2 and MSX2+ BIOSes if needed.

Thanks,
Sergey

/forum/index.php?t=getfile&id=1708&private=0
Re: MSX2 Compatible Computer Project [message #7383 is a reply to message #7329] Tue, 31 March 2020 14:16 Go to previous messageGo to next message
jordi.solis is currently offline  jordi.solis
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Hi all.
I wonder how Petr did it because even looking at the source Assembler files is hard to me imagine how.

Otherwise I fount a little problem and I would like get help also on this.
All chars are now ok but the slashbar what is yen symbol.
I think is a bit different issue because when the system should print a \ it prints a Y (yen money symbol) on its place.
So... when the DOS begins shows anything like a:Y> and not like a:\>
and when you would like to go root directory you should type cd Y (you will write the yen simbol with the \ key)

Everything works even that, but again, this is anything that looks correctly in PAL version.
I wonder if anyone can find a solution to that problem.
Maybe understanding what refers to BIOS source codes at BIOS.MAC and KEYINT.MAC

If someone can solve this, please let me know.
Jordi Solis
MSXmakers!
Re: MSX2 Compatible Computer Project [message #7384 is a reply to message #7383] Tue, 31 March 2020 14:30 Go to previous messageGo to next message
bifo is currently offline  bifo
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jordi.solis wrote on Tue, 31 March 2020 14:16
Hi all.
Otherwise I fount a little problem and I would like get help also on this.
All chars are now ok but the slashbar what is yen symbol.
I think is a bit different issue because when the system should print a \ it prints a Y (yen money symbol) on its place.
So... when the DOS begins shows anything like a:Y> and not like a:\>
and when you would like to go root directory you should type cd Y (you will write the yen simbol with the \ key)

Jordi Solis
MSXmakers!
So far as I know, that's standard behavior on Japanese MS-DOS based systems, and since MSX-DOS is derived from MS-DOS I wouldn't be worried about it. It should work and act as if it were a \
Re: MSX2 Compatible Computer Project [message #7387 is a reply to message #7384] Tue, 31 March 2020 16:31 Go to previous messageGo to next message
Sergey is currently offline  Sergey
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That is the expected behavior since Petr only modifed the keyboard mapping code. The font in the BIOS is still a Japanese one. If you look at the MSX fonts here https://www.msx.org/wiki/MSX_font, character 0x5C in the international font is "\", while in Japanese font it is yen sign.
This can be fixed by modifying the font. I'll take a stab at that later.

[Updated on: Tue, 31 March 2020 16:32]

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Re: MSX2 Compatible Computer Project [message #7390 is a reply to message #7387] Wed, 01 April 2020 23:08 Go to previous messageGo to next message
bifo is currently offline  bifo
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Sergey wrote on Tue, 31 March 2020 16:31
That is the expected behavior since Petr only modifed the keyboard mapping code. The font in the BIOS is still a Japanese one. If you look at the MSX fonts here https://www.msx.org/wiki/MSX_font, character 0x5C in the international font is "\", while in Japanese font it is yen sign.
This can be fixed by modifying the font. I'll take a stab at that later.
This raises an interesting question, have you shipped any boards to Japan? I wonder if the hobbyist culture over there is aware of this project.

MSX is a bit of a novelty for people in the US, and difficult to find in Europe and elsewhere, but it was mainstream there.
Re: MSX2 Compatible Computer Project [message #7394 is a reply to message #7390] Thu, 02 April 2020 02:31 Go to previous messageGo to next message
jordi.solis is currently offline  jordi.solis
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Hummm
I wonder if their MSX DOS always looked like this...
A:Y>

Re: MSX2 Compatible Computer Project [message #7395 is a reply to message #7394] Thu, 02 April 2020 02:49 Go to previous messageGo to next message
jordi.solis is currently offline  jordi.solis
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People,
I fount anything who can help
http:// www.msxarchive.nl/pub/msx/emulator/system_roms/nms8280-2plus -german-roms.zip
Hans Oranje did a job on the MSX2+ BIOS and adapted it to german or international standards. I will try latter if it directly works with the OMEGA. ;-)

There's a big amount info to look at on https://hansotten.file-hunter.com/do-it-yourself/msx2-upgrades/

Jordi Solis.
Re: MSX2 Compatible Computer Project [message #7396 is a reply to message #7394] Thu, 02 April 2020 06:09 Go to previous messageGo to next message
bifo is currently offline  bifo
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jordi.solis wrote on Thu, 02 April 2020 02:31
Hummm
I wonder if their MSX DOS always looked like this...
A:Y>
It's been many years since I owned a PC-9801 laptop but as I recall, the built-in basic did, and so did the DOS version used. The lines through the Y made it obvious that it wasn't a normal capital Y though so you wouldn't really notice otherwise. It was CGA on a monochrome display so the resolution was probably the same.

Honestly, I don't really understand why or how this could be a problem? The system can't tell the difference, everything treats it the exact same way. The only difference is the visual representation.

EDIT: Come to think of it, $ was a prompt for many operating systems in the past, so why would anyone find ¥ surprising is beyond me to comprehend.

[Updated on: Thu, 02 April 2020 06:12]

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Re: MSX2 Compatible Computer Project [message #7404 is a reply to message #4137] Thu, 02 April 2020 10:20 Go to previous messageGo to next message
tangent is currently offline  tangent
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It has been this way since a Japanese electronic character set was first standardized: https://en.wikipedia.org/wiki/JIS_X_0201

You can even see this in Win10 if you change your command prompt font to MS Gothic Smile
Re: MSX2 Compatible Computer Project [message #7435 is a reply to message #7404] Mon, 06 April 2020 03:30 Go to previous messageGo to next message
andrii_kutepov is currently offline  andrii_kutepov
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Hello everyone, how do you think such a device will work with Omega?
https://www.msx.org/wiki/Carnivore2
https://github.com/RBSC/Carnivore2
Re: MSX2 Compatible Computer Project [message #7450 is a reply to message #7435] Tue, 07 April 2020 06:43 Go to previous messageGo to next message
martin8bity is currently offline  martin8bity
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andrii_kutepov wrote on Mon, 06 April 2020 12:30
Hello everyone, how do you think such a device will work with Omega?
https://www.msx.org/wiki/Carnivore2
https://github.com/RBSC/Carnivore2
Sure, it does http://www.8bity.cz/2020/carnivore2-compact-flash-vce-pameti -a-lep-zvuk-pro-msx/. For audio to work you must have +/-12V power supply or another solution, such as http://www.8bity.cz/2020/power-module-12v-for-omega-home-com puter/.


www.8bity.cz

[Updated on: Tue, 07 April 2020 06:47]

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Re: MSX2 Compatible Computer Project [message #7458 is a reply to message #7450] Wed, 08 April 2020 06:40 Go to previous messageGo to next message
jordi.solis is currently offline  jordi.solis
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Thanks Martin ;-)
What about those PCBs:

https://www.msx.org/forum/msx-talk/hardware/1024kb-memory-up grade-yamaha-msx2-yis503?page=0
https://github.com/RBSC/F4-FMPAC

Does anybody tested them with the Omega Home Computer?

thanks.
Re: MSX2 Compatible Computer Project [message #7460 is a reply to message #7458] Wed, 08 April 2020 08:13 Go to previous messageGo to next message
Sergey is currently offline  Sergey
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jordi.solis wrote on Wed, 08 April 2020 06:40

https://www.msx.org/forum/msx-talk/hardware/1024kb-memory-up grade-yamaha-msx2-yis503?page=0
This one is designed specifically for Yamaha YIS503. Also, Omega already provides 512KiB RAM. If that is not enough, it can be easily extended up to 4 MiB using the connector on the right side. The schematic and the PCB would be really simple. Just connect the signals to up to 7 512 KiB SRAM ICs. All the logic is already implemented on the main board.

Quote:

https://github.com/RBSC/F4-FMPAC
This probably will work. Although it can be significantly simplified: Omega would not need a ROM for FMPAC, there's plenty of space in system flash ROM. F4 port - I am still confused as for why one would need it (maybe for Mega RAM loaders, so they can reset the system without erasing RAM content?!Wink. But if needed all the port F4 decode logic can be made into an ATF16F8 SPLD. The same SPLD can be also used for YM2413, a.k.a. OPLL.
The sound output can be fed back to Omega, so that the analog / opamp part can be omitted as well. Unless you want stereo sound.

Let me know if you're interested in either one of the options. I can help with the design.
Re: MSX2 Compatible Computer Project [message #7471 is a reply to message #7460] Thu, 09 April 2020 06:23 Go to previous messageGo to next message
bifo is currently offline  bifo
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I don't know whether the Carnivore cart will work with the omega, it overrides memory mapping and most of it really isn't necessary when you can get a Sunrise IDE cart for a third of the price and that gives you a CF card interface.

Frankly the biggest problem with the omega is the lack of a floppy drive interface, because connecting a floppy (or equivalent usb-floppy drive emulator) is the only way of actually loading any software onto the system at all. AFAIK both the sunrise and the carnivore require a floppy drive to format the CF or SD cards you'd use and you'd need to install NEXTOR/MSX-DOS on them in order to do something with them. Then you'd have to load all of the software you wanted to use on the cards via your PC.
Re: MSX2 Compatible Computer Project [message #7472 is a reply to message #7460] Thu, 09 April 2020 06:36 Go to previous messageGo to next message
bifo is currently offline  bifo
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Sergey wrote on Wed, 08 April 2020 08:13
jordi.solis wrote on Wed, 08 April 2020 06:40

Quote:

https://github.com/RBSC/F4-FMPAC
This probably will work. Although it can be significantly simplified: Omega would not need a ROM for FMPAC, there's plenty of space in system flash ROM. F4 port - I am still confused as for why one would need it (maybe for Mega RAM loaders, so they can reset the system without erasing RAM content?!Wink. But if needed all the port F4 decode logic can be made into an ATF16F8 SPLD. The same SPLD can be also used for YM2413, a.k.a. OPLL.
The sound output can be fed back to Omega, so that the analog / opamp part can be omitted as well. Unless you want stereo sound.

Let me know if you're interested in either one of the options. I can help with the design.
I mean, it's your design man, and I'm crap at all of this stuff, but a place to plug in a floppy drive and an FM chip onboard would make this possibly the best MSX clone anyone has ever actually created.

what i would wonder about is the memory mapping with regards to the FMPAC. it might require some redirects?

[Updated on: Thu, 09 April 2020 06:37]

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Re: MSX2 Compatible Computer Project [message #7473 is a reply to message #7472] Thu, 09 April 2020 07:19 Go to previous messageGo to next message
borutk is currently offline  borutk
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I really like the idea behind https://github.com/S0urceror/MSX-USB.
Similar to Rookiedrive, but open source.
You can even attach USB floppy drive if you want.
I haven't tried it yet, pcbs are still being made in China.

bo/
Re: MSX2 Compatible Computer Project [message #7503 is a reply to message #7473] Mon, 13 April 2020 02:48 Go to previous messageGo to next message
lintweaker is currently offline  lintweaker
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borutk wrote on Thu, 09 April 2020 16:19
I really like the idea behind https://github.com/S0urceror/MSX-USB.
Similar to Rookiedrive, but open source.
You can even attach USB floppy drive if you want.
I haven't tried it yet, pcbs are still being made in China.

bo/
I've also made a MSX cartridge for it:
https://slimnet.home.xs4all.nl/msxusbsd-640.jpg
Working with S0urcerer to get my board going sw wise

[Updated on: Mon, 13 April 2020 02:49]

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Re: MSX2 Compatible Computer Project [message #7505 is a reply to message #7503] Mon, 13 April 2020 06:39 Go to previous messageGo to next message
jordi.solis is currently offline  jordi.solis
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lintweaker wrote on Mon, 13 April 2020 11:48

Working with S0urcerer to get my board going sw wise
Good!
Don't forget to work also in a Symbos driver, Rookie Drive does not have compatible driver for it yet.

Regards
Re: MSX2 Compatible Computer Project [message #7506 is a reply to message #7471] Mon, 13 April 2020 07:08 Go to previous messageGo to next message
jordi.solis is currently offline  jordi.solis
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bifo wrote on Thu, 09 April 2020 15:23

AFAIK both the sunrise and the carnivore require a floppy drive to format the CF or SD cards you'd use and you'd need to install NEXTOR/MSX-DOS on them in order to do something with them. Then you'd have to load all of the software you wanted to use on the cards via your PC.
Hi,
I have all the Carnivore components but it's still in my to do list.
I'm not sure about Carnivore but with the rookie drive was easier as formatting it with windows 7 and copy all the files.
Even the best way was start on BASIC with the cartridge ROM inside and "call fdisk".
I don't know if carnivore has similar functionality but it should.

I will let you know as far as I get it working.

MSXmakers
Re: MSX2 Compatible Computer Project [message #7507 is a reply to message #7460] Mon, 13 April 2020 07:17 Go to previous messageGo to next message
jordi.solis is currently offline  jordi.solis
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[quote title=Sergey wrote on Wed, 08 April 2020 17:13]
This one is designed specifically for Yamaha YIS503. Also, Omega already provides 512KiB RAM. If that is not enough, it can be easily extended up to 4 MiB using the connector on the right side. The schematic and the PCB would be really simple. Just connect the signals to up to 7 512 KiB SRAM ICs. All the logic is already implemented on the main board.

I took a look on your connector signals right know. I just thought you made this connector for previous maiden board and so I didn't imagine you implemented all the logic on the main board.

I think you mean a design like this.
Thank you to double check it. (I'm not so confident with my skills).

MSXmakers
Re: MSX2 Compatible Computer Project [message #7508 is a reply to message #7507] Mon, 13 April 2020 08:20 Go to previous messageGo to next message
Sergey is currently offline  Sergey
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jordi.solis wrote on Mon, 13 April 2020 07:17

I took a look on your connector signals right know. I just thought you made this connector for previous maiden board and so I didn't imagine you implemented all the logic on the main board.

I think you mean a design like this.
Thank you to double check it. (I'm not so confident with my skills).
This looks good! When you design the PCB, it would be convenient if it can be connected on the right side of the main board (instead of going on the top).
But it is really up to you. Do whatever fits better in your enclosure!

The only thing I can recommend adding, is buffering on /RD and /WR signals... That is probably not really required, but won't hurt. You can use a non-inverting logic gate to buffer these. Eg. 74AHCT32, 74HCT08 connecting both inputs of an OR/AND gate together. 74AHCT244 would work too, but it is a bigger package.
Re: MSX2 Compatible Computer Project [message #7509 is a reply to message #7508] Mon, 13 April 2020 08:51 Go to previous messageGo to next message
jordi.solis is currently offline  jordi.solis
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Sergey wrote

F4-FMPAC This probably will work.
I ordered few F4-FMPAC boards to be built, so I will be able to test at all if it's working or not.

Quote:

Although it can be significantly simplified:
Omega would not need a ROM for FMPAC, there's plenty of space in system flash ROM.
I will try to glue it myself. Rolling Eyes
Quote:

F4 port - If needed all the port F4 decode logic can be made into an ATF16F8 SPLD.
A hint to do it by myself would be good, It's easy to program a SPLD as replacement for a sequential logic (74LS74D)? Maybe I should consider the clock on the karnaugh's table?
Quote:

The same SPLD can be also used for YM2413, a.k.a. OPLL.
I will need to check it's datasheet, I wonder it was so simple.
Quote:

The sound output can be fed back to Omega, so that the analog/opamp part can be omitted as well.
So all that can be replaced by an SPLD and reprogramming the ROM?
Quote:

Unless you want stereo sound.
I think it would be nice even some jumpers to select it. The worst thing is RGB connector has not spare pins for adding the stereo sound. Very Happy

Quote:

I can help with the design.
I would be glad to get your help

Thanks.
MSXmakers

Re: MSX2 Compatible Computer Project [message #7510 is a reply to message #7509] Mon, 13 April 2020 12:22 Go to previous messageGo to next message
jordi.solis is currently offline  jordi.solis
Messages: 114
Registered: March 2017
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As comented on the following web page:
https://hansotten.file-hunter.com/do-it-yourself/msx2-upgrades/Quote:

Add the F4 register required by Basic 3.0
Maybe we fount the only use for this F4 register
Kind regards.
MSXmakers
Re: MSX2 Compatible Computer Project [message #7511 is a reply to message #7509] Mon, 13 April 2020 12:43 Go to previous messageGo to next message
Sergey is currently offline  Sergey
Messages: 236
Registered: October 2015
Location: Portland, OR
Senior Member
jordi.solis wrote on Mon, 13 April 2020 08:51

I ordered few F4-FMPAC boards to be built, so I will be able to test at all if it's working or not.
Keep us posted!

Quote:
Quote:
F4 port - If needed all the port F4 decode logic can be made into an ATF16F8 SPLD.
A hint to do it by myself would be good, It's easy to program a SPLD as replacement for a sequential logic (74LS74D)? Maybe I should consider the clock on the karnaugh's table?
Well, you'll still need to use an external 74*74 flip-flop. While it is possible to implement registered logic in the SPLD, there is no way to reset it at power on.
Something like this should work (equations for GALasm):

; FM chip select; FM I/O ports - 0x7C and 0x7D
/FMCS = /IORQ * M1 * /A7 * A6 * A5 * A4 * A3 * A2 * A1
; F4 port write - 0xF4 (connect to 74*74 CLK)
/F4WR = /IORQ * M1 * A7 * A6 * A5 * A5 * /A3 * A2 * /A1 * A0 * /WR
; FM port read - 0xF4 (connect to SPLD OE pin 11)
/F4RD = /IORQ * M1 * A7 * A6 * A5 * A5 * /A3 * A2 * /A1 * A0 * /RD
; F4 register output (connect D7 to D7 of cartridge, connect F4_Q to 74*74 Q output)
D7.T = /F4RD * F4_Q

Quote:
Quote:
The same SPLD can be also used for YM2413, a.k.a. OPLL.
I will need to check it's datasheet, I wonder it was so simple.
I didn't mean to implement the Y2413 in the SPLD, but just to implement the chip select logic - a replacement for IC2 and IC3 on the schematic. See equations above.

Quote:
The sound output can be fed back to Omega, so that the analog/opamp part can be omitted as well.
Just connect the SLT signal (see F4-FMPAC) schematic to slot pin #49, or through an RC (10 uF capacitor + 4.7 kOhm resistor) to pin 2 of U48 op amp on Omega. In this case single op amp can be used (the second op amp is used to buffer the signal for connecting external amplifier)

Quote:
Quote:

Unless you want stereo sound.
I think it would be nice even some jumpers to select it. The worst thing is RGB connector has not spare pins for adding the stereo sound. Very Happy
Actually OPLL produce mono output... so this is not relevant

Quote:
Quote:
I can help with the design.
I would be glad to get your help
I need to find a couple of hours. How about making a cartridge with F4 and FM-PAC, and perhaps a WD37C65 floppy controller?!
Re: MSX2 Compatible Computer Project [message #7512 is a reply to message #7510] Mon, 13 April 2020 12:49 Go to previous messageGo to next message
Sergey is currently offline  Sergey
Messages: 236
Registered: October 2015
Location: Portland, OR
Senior Member
jordi.solis wrote on Mon, 13 April 2020 12:22
As comented on the following web page:
https://hansotten.file-hunter.com/do-it-yourself/msx2-upgrad es/Quote:

Add the F4 register required by Basic 3.0
Maybe we fount the only use for this F4 register
It is not required by BASIC 3.0. It would work regardless. I've tried ;-)
The only benefit seems to be the ability of warm resetting the system without clearing the memory content. Which might be used by RAM mapper to launch the emulated mega ROM? maybe? Don't know...
Re: MSX2 Compatible Computer Project [message #7514 is a reply to message #7511] Mon, 13 April 2020 17:36 Go to previous messageGo to next message
jordi.solis is currently offline  jordi.solis
Messages: 114
Registered: March 2017
Senior Member
Hi,
I will start working on this tomorrow.

Sergey wrote on Mon, 13 April 2020 21:43

Actually OPLL produce mono output... so this is not relevant
I'm pretty sure YM2149 can produce stereo sound as shown in the N8 or SCGS schematics.
Is a circuit quite similar to the one attached by me. If I'm not wrong CN10 is an stereo output jack, connected to the YM2413 outputs.

Quote:

How about making a cartridge with F4 and FM-PAC, and perhaps a WD37C65 floppy controller?!
Sounds good.
I have also pending to build a Multicontroller board.
But my own goal is to have a long hat over the mainboard, like a 2nd floor with a turbo speed button selection, a WD35C65 floppy & IDE controller, an F4-FMPACK sound improvement, and seven AS6C4008 to extend the RAM. Of course all through hole.
My case was design to fit a floppy drive from the beginning.

MSXmakers.
Re: MSX2 Compatible Computer Project [message #7531 is a reply to message #7514] Tue, 14 April 2020 23:00 Go to previous messageGo to next message
Sergey is currently offline  Sergey
Messages: 236
Registered: October 2015
Location: Portland, OR
Senior Member
I've updated the make_roms.sh in the GitHub repository. Now it includes the patch to replace the yen sign with the backslash. It also includes the patch for the ROM flags (locations 0x2B and 0x2C) to indicate International rather than Japanese ROM. This can be useful in some cases, but harmful in others. For example some Konami games use these flags to switch between Japanese and English (Vampire Killer, The Treasure Of Usas), while others will not work on non Japanese-machine (Metal Gear).

Here is the list of the currently produced ROM images:

  • omega_msx2_ntsc.bin - MSX2 ROM based on Sanyo PHC-23J, international keyboard, patched backslash; and US/NTSC MSX2 C-BIOS
  • omega_msx2_pal.bin - MSX2 ROM based on Philips NMS 8250; and EU/PAL MSX2 C-BIOS
  • omega_msx2+_ntsc.bin - MSX2+ ROM based on Sanyo PHC-35J, international keyboard, patched backslash; and US/NTSC MSX2+ C-BIOS
  • omega_msx2_int_ntsc.bin - MSX2 ROM based on Sanyo PHC-23J, international keyboard, patched backslash; and the same BIOS with "international" flags set
  • omega_msx2_msx2+_ntsc.bin - MSX2+ ROM based on Sanyo PHC-35J, international keyboard, patched backslash; and the same BIOS with "international" flags set
  • omega_msx2+_int_ntsc.bin - MSX2 ROM based on Sanyo PHC-23J, international keyboard, patched backslash, with "international" flags set; and MSX2+ ROM based on Sanyo PHC-35J, international keyboard, patched backslash
I personally run the last image on my machine, as it provides multiple combinations: MSX2 and MSX2+, Japanese vs. International.
It should be fairly easy to modify the make_roms.sh script to generate whatever image variety you'd like. If you don't have Linux machine, I presume the script should be working in Cygwin environment. Otherwise feel free to PM me for a binary image.

Cheers,
Sergey

Re: MSX2 Compatible Computer Project [message #7538 is a reply to message #7506] Wed, 15 April 2020 20:36 Go to previous messageGo to previous message
bifo is currently offline  bifo
Messages: 48
Registered: October 2019
Member
jordi.solis wrote on Mon, 13 April 2020 07:08
bifo wrote on Thu, 09 April 2020 15:23

AFAIK both the sunrise and the carnivore require a floppy drive to format the CF or SD cards you'd use and you'd need to install NEXTOR/MSX-DOS on them in order to do something with them. Then you'd have to load all of the software you wanted to use on the cards via your PC.
Hi,
I have all the Carnivore components but it's still in my to do list.
I'm not sure about Carnivore but with the rookie drive was easier as formatting it with windows 7 and copy all the files.
Even the best way was start on BASIC with the cartridge ROM inside and "call fdisk".
I don't know if carnivore has similar functionality but it should.

I will let you know as far as I get it working.

MSXmakers
That's great news, thanks. My Sunrise CF adapter finally arrived and doesn't fit the slot in my old MSX2, so I'm kind of at a loss on how to move forward. I'll hopefully finish the Omega by the end of this month and can experiment with that. Either that, or remove the front of my old MSX2. The slot would fit the cartridge fine, but the design of the Sunrise is frustratingly off-center.
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