nevets14
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Joined: 11 Jul 2018, 23:14

Re: Terraonion announces the MegaSD FPGA Sega CD/Mega-CD for your Megadrive and Genesis

19 Jun 2019, 00:35

pfitz1982 wrote:
19 Jun 2019, 00:05
Can the Mega SD play Sega LD games?
Unless the MegaSD can replicate the LD video capabilities, then no.

L-Digital
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Joined: 13 Apr 2018, 22:29

Re: Terraonion announces the MegaSD FPGA Sega CD/Mega-CD for your Megadrive and Genesis

19 Jun 2019, 23:43

Ok, I have my pre-order but I am super confused about how this works with the 32x.
I have watched the video and read the manual and from what I can see, the 32x needs to be removed to use the CD functionality? is this correct?
From the manual it says I could play CD games if I have the special adaptor, but then it cant play cartridge games. Will there be more info on this adaptor?

Is there no solution that can play CD, MD and 32X carts without having to plug and unplug things?

am I getting the the total wrong end of the stick here?

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Todd
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Re: Terraonion announces the MegaSD FPGA Sega CD/Mega-CD for your Megadrive and Genesis

20 Jun 2019, 02:14

No. You are correct.

There is simply no way to play cd games through the 32x cart slot. The signals aren’t present that we need.

And the side expansion port won’t allow SMS games to work at all. And genesis cart rom size is limited to, I believe, 256kb. So we disabled that as it would it wouldn’t make sense.

mario64
Posts: 13
Joined: 18 Jun 2019, 20:47

Re: Terraonion announces the MegaSD FPGA Sega CD/Mega-CD for your Megadrive and Genesis

22 Jun 2019, 17:46

Todd wrote:
20 Jun 2019, 02:14
No. You are correct.

There is simply no way to play cd games through the 32x cart slot. The signals aren’t present that we need.

And the side expansion port won’t allow SMS games to work at all. And genesis cart rom size is limited to, I believe, 256kb. So we disabled that as it would it wouldn’t make sense.
Hi Todd. Did (or could) the Engineers investigate the possibility of modding the 32x to allow it to work with Mega SD? There are reports of a user getting SMS games to work which would seem to indicate it is possible to configure it to provide the signals you need.

Mobiusstriptech
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Joined: 13 Apr 2018, 15:41

Re: Terraonion announces the MegaSD FPGA Sega CD/Mega-CD for your Megadrive and Genesis

23 Jun 2019, 03:21

Modding the 32x to pass through the required signals is technically possible. However, you will have a real hard time finding someone to do it if you can't do it yourself. The cost to mod a 32x to pass SMS games is going to be quite high. I am fairly certain that the necessary mod for the MegaSD will be the same or possibly include a couple additional signals.

mario64
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Joined: 18 Jun 2019, 20:47

Re: Terraonion announces the MegaSD FPGA Sega CD/Mega-CD for your Megadrive and Genesis

23 Jun 2019, 23:49

Mobiusstriptech wrote:
23 Jun 2019, 03:21
Modding the 32x to pass through the required signals is technically possible. However, you will have a real hard time finding someone to do it if you can't do it yourself. The cost to mod a 32x to pass SMS games is going to be quite high. I am fairly certain that the necessary mod for the MegaSD will be the same or possibly include a couple additional signals.
Thanks Mobius. That's very disappointing.

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neodev
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Re: Terraonion announces the MegaSD FPGA Sega CD/Mega-CD for your Megadrive and Genesis

04 Jul 2019, 08:43

Modding the 32x to bypass the signals needs a lot of wiring. I was thinking about it some days ago, and what you need is to wire the 16 data signals from the console (male connector), pass them through a bidirectional buffer (74xx16245 5V TTL chip) and then from the chip outputs to the cart (female) conector 16 data lines. It will also need power (5V and gnd from the console connector), the direction signal (Read signal from the console connector) and the signal that indicates the console is accessing the CD registers block. Unfortunately that signal is only present on the expansion connector so you need to pass a wire from that pin in the exp connector, or add some logic to check if the high 12 bits of the address are A12, thus needing another 12 wires. It's a big mess, and that's assuming that when a write happens, the cart data lines in the 32x female connector are left undriven (which is likely).
And then you need to add the SMS address bypass too.

samson7point1
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Joined: 17 Apr 2018, 01:17

Re: Terraonion announces the MegaSD FPGA Sega CD/Mega-CD for your Megadrive and Genesis

10 Aug 2019, 05:25

neodev wrote:
04 Jul 2019, 08:43
Modding the 32x to bypass the signals needs a lot of wiring. I was thinking about it some days ago, and what you need is to wire the 16 data signals from the console (male connector), pass them through a bidirectional buffer (74xx16245 5V TTL chip) and then from the chip outputs to the cart (female) conector 16 data lines. It will also need power (5V and gnd from the console connector), the direction signal (Read signal from the console connector) and the signal that indicates the console is accessing the CD registers block. Unfortunately that signal is only present on the expansion connector so you need to pass a wire from that pin in the exp connector, or add some logic to check if the high 12 bits of the address are A12, thus needing another 12 wires. It's a big mess, and that's assuming that when a write happens, the cart data lines in the 32x female connector are left undriven (which is likely).
And then you need to add the SMS address bypass too.
It seems like it would be more worthwhile to develop a version of the MegaSD that was just installed internally to the Genesis/Mega Drive. That way it would have access to all of the signal lines BEFORE the 32x and would not be limited by the expansion port.

mario64
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Joined: 18 Jun 2019, 20:47

Re: Terraonion announces the MegaSD FPGA Sega CD/Mega-CD for your Megadrive and Genesis

10 Aug 2019, 17:19

Todd wrote:
18 Jun 2019, 21:18
mario64 wrote:
18 Jun 2019, 20:52
Question for the devs. Does Mega SD support Pier Solar? I own the cartridge but would prefer to play via flash cart. Problem is, Mega ED X7 does not support this game

On a related note, if Pier Solar is supported can you load the soundtrack disc via Mega SD and play with CD audio?

Thanks

Yes and Yes!

Place the Pier Solar rom into the same folder as the CD Bin+Cue. On the MegaSD menu you will see a little Icon that says 'MD+' signifying an enhanced game.
Now that I have my Mega SD I unfortunately have to report that Pier Solar in fact does not work with the enhanced soundtrack disc. I did just as you instructed. Placed the rom and CD Bin + Cue into a folder. Mega SD shows the MD+ icon. However, when the game launches and you go to the Options menu you don't get the "Disc ready!" indicator as you do on real hardware. This is what indicates the cartridge recognizes and will use the soundtrack disc. This simply does not happen on Mega SD. Very disappointed :-(

EDIT: Never mind. I changed to the 2.00W BIOS as recommended and it now works perfectly. I was previously using the CDX BIOS file.

Pupil
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Joined: 18 Aug 2019, 04:09

Re: Terraonion announces the MegaSD FPGA Sega CD/Mega-CD for your Megadrive and Genesis

20 Aug 2019, 02:03

L-Digital wrote:
19 Jun 2019, 23:43
From the manual it says I could play CD games if I have the special adaptor, but then it cant play cartridge games. Will there be more info on this adaptor?
I'm a bit confused. I thought the Mega SD could play Sega CD games on just the cart without any additional adapter? Am I missing something?

EDIT: Okay I watched the video. It looks like that adapter would only be to play 32x CD games.

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