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!!Success!! Help with USB EPROM Writer
Post Posted: Wed Mar 11, 2015 8:41 pm
Last edited by TheSegaDude on Tue Jul 07, 2015 5:24 pm; edited 1 time in total
Hi guys,

I'd like some advice.

I have a loose cart for both the SMS Phantasy Star and the Japanese Mega Drive Phantasy Star (Fukkokuban).

I want to replace the ROM on each with an EPROM containing the SMS Power English translation.

I would like to be able to do the work myself (at least try).
Could someone recommend an appropriate USB EPROM Writer and the name of the EPROMs I would need?

Maybe I'll even take this step further and dump the ROM myself instead of just applying the IPS patch to a downloaded ROM.
In that case could you guys also give me a few pointers on dumping the ROMs?

My soldering skills are very limited but recently I have installed four new EL Panels into my Neo Geo MVS Cabinet and installed a FM Sound unit into my Master System so I think stand a chance at doing this.

Thanks!
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Post Posted: Thu Mar 12, 2015 5:06 pm
For EEPROM write I suggest the TL866CS. I use this extensively on my projects.

As for the EEPROM, or Flash I should say since this is mostly likely what you'll end up using. You will probably not find something that matches the pinout of your Phantasy Star cart. Furthermore, a lot of SMS games had the Mapper and ROM combined in a single IC. See Building a Rewritable Cartridge in the Development section for more information about this. You'll have to find a suitable game which has the Mapper and ROM in seperate ICs, AND, supports save features (for Phantasy Star).

I'm working on building a new SMS cart with all these features, I'm nearing completion and hopefully will be able to make an announcement soon.
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Post Posted: Thu Mar 12, 2015 5:44 pm
Phantasy Star cartridges all have separate mappers and SRAM, as far as I know.
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Post Posted: Thu Mar 12, 2015 5:45 pm
Maxim wrote
Phantasy Star cartridges all have separate mappers and SRAM, as far as I know.


Well that's excellent news for TheSegaDude!
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Post Posted: Thu Mar 12, 2015 7:47 pm
Hi db-electronics and Maxim!

First off, thank you very much for taking the time to answer.
I know I lack a lot of knowledge for this kind of thing and I really do appreciate you taking some time to explain things.
I'm sure it can be frustrating sometimes when chatting with newbies like me :)

db-electronics I'll take your advice and purchase a MiniPro USB TL866CS Universal Programmer.
But first I want to be sure I can purchase the ICs that I'll need.

Where can I buy an EEPROM that will work for the Phantasy Star cart? (for the SMS cart and for the Mega Drive version)
What's the name or model of an EEPROM that will work for this?
Can something compatible still be purchased these days?
Do you know the name of a good online store that I could ask?

From Maxim's reply I'm getting the impression that I just need a EEPROM to hold the ROM and everything else (mappers and SRAM) is already on the board. Right? Is this true for both the SMS cart and Mega Drive cart?
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Post Posted: Thu Mar 12, 2015 7:58 pm
I'm not sure about the pinout of the ROM chip on the Phantasy Star cart, but generally you'll want to work with a DIP Flash IC since it would be fairly easy to wire a DIP into an incompatible pinout.

You could use an SST39SF040 which has the required 512KB of ROM for Phantasy Star - this is a modern part that is currently being manufactured. You can get these on eBay, Digikey, Mouser, etc...
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Post Posted: Thu Mar 12, 2015 8:48 pm
Thanks for the links!
I took a look and I was expecting to see ICs that are windowed.

How does the SST39SF040 work? I can write to it only once? That would be just fine by me. I'm just curious now.

db-electronics wrote
I'm not sure about the pinout of the ROM chip on the Phantasy Star cart, but generally you'll want to work with a DIP Flash IC since it would be fairly easy to wire a DIP into an incompatible pinout.

You could use an SST39SF040 which has the required 512KB of ROM for Phantasy Star - this is a modern part that is currently being manufactured. You can get these on eBay, Digikey, Mouser, etc...
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Post Posted: Thu Mar 12, 2015 8:54 pm
TheSegaDude wrote
Thanks for the links!
I took a look and I was expecting to see ICs that are windowed.


Those are UV EEPROMs and they're as old as the earth - not modern nor readily available from reputable distributors. EEPROM today has generally been superseded by Flash.

TheSegaDude wrote
How does the SST39SF040 work? I can write to it only once? That would be just fine by me. I'm just curious now.


SST39SF0x0 is flash, much like (but not quite) in a USB thumb drive. It can be rewritten thousands of times.
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Post Posted: Fri Mar 13, 2015 11:32 am
TheSegaDude wrote

I have a loose cart for both the SMS Phantasy Star and the Japanese Mega Drive Phantasy Star (Fukkokuban).


If you can post a (or some) picture(s) of the PCB, i'll be very interested!


@Maxim,
all PS cart i've got (3 europeans) have "unfortunately" the mapper within the rom.
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Post Posted: Fri Mar 13, 2015 2:23 pm
OK, I take that back :)
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Post Posted: Fri Mar 13, 2015 8:48 pm
OK, I'll post some pictures this weekend.

I would love it if you guys could help me identify what chip I need to buy to make this work. Just in case I need something different than what db-electronics gave me links for.

@db-electronics. I did order the USB MiniPro TL866CS that you recommended but it will take some time for it to arrive.

Thanks for your input on this!

ichigobankai wrote
TheSegaDude wrote

I have a loose cart for both the SMS Phantasy Star and the Japanese Mega Drive Phantasy Star (Fukkokuban).


If you can post a (or some) picture(s) of the PCB, i'll be very interested!


@Maxim,
all PS cart i've got (3 europeans) have "unfortunately" the mapper within the rom.
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Post Posted: Sat Mar 14, 2015 3:49 pm
OK, here are some pictures of the PCBs for Phantasy Star for both the Master System and Mega Drive.

Are you able to tell if the mappers are built into these ROM chips?

If so is there a modern EEPROM/Flash chips I can buy to do the trick?

Would you guys be able to help identify each of the ICs on the boards? I'm not even sure which are the ROMs and which are the mappers.
I have however been able to identify the battery :D
Phantasy Star for MD and SMS PCB.jpg (2.53 MB)
Both original cartridges.
Phantasy Star for MD and SMS PCB.jpg
Phantasy Star Fukkokuban MD PCB 01.jpg (2.48 MB)
PS Fukkokuban Front
Phantasy Star Fukkokuban MD PCB 01.jpg
Phantasy Star Fukkokuban MD PCB 02.jpg (2.72 MB)
PS Fukkokuban Back
Phantasy Star Fukkokuban MD PCB 02.jpg
Phantasy Star SMS PCB 01.jpg (2.67 MB)
PS SMS Front
Phantasy Star SMS PCB 01.jpg
Phantasy Star SMS PCB 02.jpg (2.68 MB)
PS SMS Back
Phantasy Star SMS PCB 02.jpg

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Post Posted: Sat Mar 14, 2015 6:01 pm
You're in luck with the SMS cart. MPR means a ROM in all Sega games. 315-5235 is a mapper chip, and this third chip is the save RAM. Charles MacDonald wrote a guide for this exact board:

http://dreamjam.co.uk/emuviews/smsflash.php

The Mega Drive one seems to have an integrated mapper. The top chip is also found in the Power Base Converter, leaving the save RAM, ROM+mapper with MPR on it, and the little chip is related to the battery backup.
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Post Posted: Sat Mar 14, 2015 6:05 pm
You're lucky each cartridge have a mapper !

so roms are MPR-XXXXXX

on fukkokuban, very interesting they're using a pal (PLS153N) to make a mapper (315-5342).
You can certainly read/dump the rom (MPR-xxx) choosing 27c040/27c4001 in your eprom burner.

edit. Maxim was faster ^^
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Post Posted: Sat Mar 14, 2015 7:45 pm
So I checked out the guide Maxim linked to:

http://dreamjam.co.uk/emuviews/smsflash.php

This leaves me to think that I cannot just solder in the new IC (SST39SF040) and have it work. Right?

From Charles' Guide he states that Pin 1 and Pin 31 are:

Original ROM (MPR-11711AT 4882-D955 9014EBI)
Pin 1 = N.C.
Pin 31 = A18

**Is there a full mapping somewhere? Do I need to check every Pin to the new IC SST39SF040?**

Where as the IC that I have ordered (SST39SF040-70-4C-PHE) is:
Pin 1 = A18
Pin 31 = VDD

Again from Charles' guide I think Pin 31 needs to be bent out (not soldered to the PCB). And it sounds like Pin 1 needs to be bridged to PIN 31 with a wire. I'll admit I'm confused here.

@ichigobankai When you say "choosing 27c040/27c4001 in your eprom burner" does that mean these modern ICs can have their pinouts written to them just like ROM software?
So that I don't have to worry about the Pin outs after having the writer tell the IC what to 'emulate'?

Again, thanks guys for taking the time to educate me!
SST39SF040-70-4C-PHE.jpg (286.5 KB)
Pin Out mapping of SST39F040
SST39SF040-70-4C-PHE.jpg

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Post Posted: Sat Mar 14, 2015 7:54 pm
use a 27C040 / 27C4001.
they are UV eproms but the pinout is 100% the same as the maskrom.

but if you really want to use a 39SF040, you'll need to :
- lift pin #31 (/WE) and connect it to VCC (pin #32) to disable it.
- connect pin #1 (A18) to maskrom hole #31
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Post Posted: Sat Mar 14, 2015 8:02 pm
Excellent.
I am trying to order them from here:

https://www.futurlec.com/Memory/27C040-100.shtml

Does anyone know of another source? The link above might not have stock. I've just emailed them to find out.
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Post Posted: Sat Mar 14, 2015 8:08 pm
you can find/buy eproms directly on ebay ;)

btw be careful, UV eprom needs to be erased (with UV eraser) if programming fails or if they are not "empty" (before programming)
39SF are erased electricaly (very fast)
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Post Posted: Sun Mar 15, 2015 10:39 pm
ichigobankai wrote
you can find/buy eproms directly on ebay ;)

btw be careful, UV eprom needs to be erased (with UV eraser) if programming fails or if they are not "empty" (before programming)
39SF are erased electricaly (very fast)


This is why I prefer Flash, even if the pinout may be different.
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Post Posted: Mon Mar 16, 2015 7:00 pm
ebay, you say?! :)

I did end up buying the MiniPro USB TL866CS and UV eraser from ebay.
The chips I found cheaper from other sites... one being your recommendation from http://www.digikey.ca.

I'm very excited about this little project!

All I can do at the moment is prepare the ROM. I know I can use Lunar IPS to apply the patch to the ROM but does anyone have a recommendation for how to verify the ROM in Windows?

This is what I've read:

The original, unmodified game has the following characteristics:

Size: 512KB (524,288 bytes)
CRC32: 6605D36A
MD5: DFEBC48DFE8165202B7F002D8BAC477B

I have not been able to find a utility for Windows that can check CRC and MD5.

Thanks again guys! I would be totally suck without your help!

ichigobankai wrote
you can find/buy eproms directly on ebay ;)

btw be careful, UV eprom needs to be erased (with UV eraser) if programming fails or if they are not "empty" (before programming)
39SF are erased electricaly (very fast)
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Post Posted: Mon Mar 16, 2015 7:05 pm
You should be able to use SMSCheck on your ROM - that would check the game's own checksum to ensure that it can pass the BIOS check.
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Post Posted: Mon Mar 16, 2015 8:05 pm
One quick and dirty way to compute a CRC is to zip the file and then use the zip tool to list the CRC (usually a hidden column). There's lots of tools for doing the MD5sum, but you're less likely to have them already installed, and the CRC check is good enough.
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Post Posted: Mon Mar 16, 2015 8:11 pm
I'd love to know of any MD5sum programs for Windows that you would recommend. I think it would be worth while having one installed.
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Post Posted: Mon Mar 16, 2015 8:31 pm
Cygwin...

At the opposite end of the spectrum, try http://code.kliu.org/hashcheck/
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Post Posted: Tue Mar 17, 2015 2:19 pm
I'm going to check out HashCheck Shell Extension first.
Thanks for the pointer!

What type of solder would you guys recommend?

I've have 1.2mm 60/40 Rosin Core solder. The label says it's for PC Work. Which I thought implied working with PCBs?

Of all Rosin Core solders does anything really matter other than the diameter?

Is there any reason why I should use flux with non-Rosin Core solder instead?

So far I've received the two flash ICs (one is spare) for the Mega Drive Phantasy Star. They have the correct number of pins and the spacing of the pins is almost an exact match to the old IC. It's so close that I don't think I'll have any trouble inserting it on the board. I wont remove the old IC until I've copied the patched ROM to the new IC (baby steps).
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Post Posted: Tue Mar 17, 2015 2:28 pm
TheSegaDude wrote
What type of solder would you guys recommend?

I've have 1.2mm 60/40 Rosin Core solder. The label says it's for PC Work. Which I thought implied working with PCBs?

Of all Rosin Core solders does anything really matter other than the diameter?


I stay away from Rosin Core solders as they tend to be corrosive in the long-term. I also dislike 60/40 solder because it doesn't solidify at a single temperature point. This can cause all sorts of problems in your solder joints.

Really, everyone should be using eutectic solder (63/37).
Wikipedia wrote
For certain proportions an alloy becomes eutectic and melts at a single temperature; non-eutectic alloys have markedly different solidus and liquidus temperatures, and within that range they exist as a paste of solid particles in a melt of the lower-melting phase. In electrical work, if the joint is disturbed in the pasty state before it has solidified totally, a poor electrical connection may result; use of eutectic solder reduces this problem. The pasty state of a non-eutectic solder can be exploited in plumbing as it allows molding of the solder during cooling, e.g. for ensuring watertight joint of pipes, resulting in a so-called 'wiped joint'.


As for core, I always recommend No Clean solder because it's just that - no cleaning required. Rosin and Water-Soluble solders MUST be cleaned. Rosin core is very difficult to clean and from my experience water-soluble can have very negative effects on the electrical performance of your circuit.

tl;dr
use 63/37 no-clean solder
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Post Posted: Tue Mar 17, 2015 3:31 pm
I will check this out as well db-electronics. Thank you!

On a side note I'm noticing that you're into building a lot of cool stuff for retro consoles.

Are you still working on your Power Base converter with FM Sound?
Are you selling it already?

db-electronics wrote
You should be able to use SMSCheck on your ROM - that would check the game's own checksum to ensure that it can pass the BIOS check.
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Post Posted: Tue Mar 17, 2015 3:39 pm
TheSegaDude wrote

Are you still working on your Power Base converter with FM Sound?
Are you selling it already?


I completed work on it last summer. It's being sold at a number of places including:

My website
Stone Age Gamer
Bit Games

I'd like to add a ROM intercept routine that could intercept the region check in games like Wonder Boy III (similar to my intercept of region check on TG-16 games for Turbo PC-Henshin) but alas that requires time.
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Post Posted: Tue Mar 17, 2015 4:20 pm
I just sent you a PM!

Does 'intercept the region check' mean the converter would make all SMS games region free? That would be really slick!
But I don't think there too many SMS games with region locks, right?
Unlike a TG-16 that can't play any Japanese HuCards.

I think I'm hijacking my own thread!
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Post Posted: Tue Mar 17, 2015 8:18 pm
A few games only enable FM if the system is Japanese (and has an FM chip). That's what needs patching if you are trying to have FM music.
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Post Posted: Sun Mar 29, 2015 1:05 am
OK, so my first attempt is a fail.

When I power on my Genesis I get nothing. No SEGA logo. Nothing but a black screen with no sound.

I received the Universal Programer and flash IC for the Mega Drive Phantasy Star so I started with Phantasy Star Fukkokuban.

I did not dump my own ROM. I'm still not sure how.

I downloaded the Japanese ROM from some random site as well as from the pscave.com. The MD5 checksum was the same for each.

I then download the already English translated ROM from pscave.com and compared it's MD5 checksum to the Japanese ROM that I patch myself.
Both checksums were identical.

Translated ROM MD5: a0f614f26e99633493e3a3339bc85586
Japanese ROM MD5: dfebc48dfe8165202b7f002d8bac477b

Does anyone know if these are correct? Is my ROM good?

I believe I loaded and wrote the ROM to the IC correctly but I'm so new at this I could have messed something up.

The next big variable is my solder skills. It seemed to have gone OK but I just don't have the experience to know for sure.

Would you guys have some advice for me?
I would like to try again! :)
File Load Options.png (108.86 KB)
Options after selecting ROM image.
File Load Options.png
Soldered ROM 01 Front.jpg (1.24 MB)
Installed ROM Front.
Soldered ROM 01 Front.jpg
Soldered ROM 02 Back.jpg (1.34 MB)
Installed ROM Back.
Soldered ROM 02 Back.jpg
Soldered ROM 03 Close.jpg (1.36 MB)
Installed ROM Close.
Soldered ROM 03 Close.jpg

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Post Posted: Sun Mar 29, 2015 7:29 am
you've completely forgotten 1 thing :

39SF040 is not 100% compatible with a master system maskrom pinout !

find the 39sf040 pinout and compare it to a 27C4001 (or 27C040) which IS a master system maskrom pinout (pinout where you have a mapper which handle at least 256ko)

short version :
- lift pin #31 (/WE)
- solder pin #32 and #31 together (VCC + /WE) to inhibit write feature.
- solder pin #1 (A18 on 39SF040) to hole 31.
you can leave pin #1 soldered on maskrom because in this place nothing is connected

PS. you must verify checksum through maxim's Header Reader soft and correct it with an hexadecimal editor before soldering anything.
If the checksum is wrong the game will never boot up on real hardware.
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Post Posted: Tue Mar 31, 2015 6:16 pm
Hey ichigobankai.

I was so pleased to see your reply! What a huge step that I overlooked!
I've been told before that 39SF040 is not 100% compatible but I still forgot.

Thank you very much for the details. I'm going to look up the pinout for both 39sf040 and 27C4001so that I can follow the steps you listed.

I'll also use maxim's Header Reader to check my ROM.

I should have a chance to try again this weekend.
I'll post again when I've made my next attempt.

Thank you!
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Post Posted: Thu Apr 02, 2015 1:06 am
Sorry to be the bearer of bad news but the 315-5342 (on the Mega Drive PS1 cartridge) is not a mapper chip. The mapper is internal to the MPR-16266-F (it's an MB834011, an custom chip which has MASK ROM + SEGA mapper built in a single die).

315-5342 is the PLD chip used on the Power base converter to set up the CPU stack before executing the game.

So basically, the MD one won't work for you.
DSC02493.JPG (184.42 KB)
315-5342
DSC02493.JPG

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Post Posted: Thu Apr 02, 2015 7:28 am
Yes, that's what I said... It doesn't even have enough pins for a mapper, they need at least 26 or so.
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Post Posted: Thu Apr 02, 2015 11:53 am
So the original Mega Drive Phantasy Star has the mapper built into the MPR-16266-F IC?
And the replacement flash IC that I have (39SF040) does not?

Is there a modern IC I can buy that will work?

What do you guys think my options are?
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Post Posted: Thu Apr 02, 2015 1:10 pm
TheSegaDude wrote
So the original Mega Drive Phantasy Star has the mapper built into the MPR-16266-F IC?
And the replacement flash IC that I have (39SF040) does not?

Is there a modern IC I can buy that will work?

What do you guys think my options are?


Your sole (practical) option is put the mask rom back and cease tampering with the MD cartridge.

You can play the SMS one on the MD using a power base adapter anyway.
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Post Posted: Thu Apr 02, 2015 1:10 pm
Not many options... You could take a mapper from another game and try to add it in, but the connections would be nightmarish.
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Post Posted: Thu Apr 02, 2015 3:42 pm
I know there are easier ways to play this translated PS1 but I'm enjoying the work so far. This project is the hobby.

If it's possible I would really like to get this method going. I'd love to have a dedicated cart for this version that's plays on the Genesis as a Genesis cart.

So, at the moment I'm OK with being unpractical.

l_oliveira wrote
Your sole (practical) option is put the mask rom back and cease tampering with the MD cartridge.

You can play the SMS one on the MD using a power base adapter anyway.


Are these mappers so old that they are not made anymore? I'd like to avoid harvesting other carts if possible.

If I had a mapper where could I read/learn about how to map it to the IC (39SF040)? I realize this might be a tall order and possibly not possible for someone with my lack of expertise.

Maxim wrote
Not many options... You could take a mapper from another game and try to add it in, but the connections would be nightmarish.


Did Sega ever repair carts with EPROMs? Would it be possible to hunt down a windowed IC that is identical to PS1 Mega Drive IC?

As always. Thanks to everyone for sharing your knowledge here. Even if it ends up that it just can't be done I'm already very pleased that I've actually made an attempted.

I've taken something past the 'day dreaming' phase and with your help I have made an attempt! And I'd like to try again.
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Post Posted: Fri Apr 03, 2015 3:52 pm
I'm very very sorry SegaDude !
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Post Posted: Wed Apr 15, 2015 1:04 am
I haven't given up yet. I'm going to try the same thing with the Sega Master System Phantasy Star.

I did receive my UV EPROM eraser but it arrived broken. So I'm going to have to get another one before I can proceed. This broken one took a very long time to arrive and I'm hoping the next one will be faster.

I'll post again when I've had a chance to do this.
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Post Posted: Wed Jun 03, 2015 6:51 pm
Small update.

I fixed my UV eraser. It needed a new switch so I could turn it on.

I'm able to read and write to the flash IC that I now know will not work with the Mega Drive Phantasy Star because there is no integrated mapper.

I moved onto the SMS Phantasy Star... I bought two 27C040 ICs and my writer can not see either of them. I cleaned the legs just in case the ICs weren't making good contact. Then I put one IC into my UV eraser for 15min. The IC still could not be seen. Could both my 27C040 ICs be bad?

I'm too inexperienced to know how to figure that out.

So I'm going to get someone who knows what there doing to burn the ROM for me. When I receive them I'll solder one into the SMS PCB and try it out.
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Post Posted: Tue Jul 07, 2015 5:23 pm
Success!

I now have the SMS Power Phantasy Star on a dedicated cart for my Sega Master System.

I wanted to post again and thank everyone here for the help you gave me. There is no way I would have been able to get this done without you.

My MiniPro IC programmer seems to read some chips and not others so I ended up have Fox1 over at the neo-geo.com forums write the EPROM for me.

When I received it I solder it into the Phantasy Star PCB and it's working!

I recorded about 1 hour 20 minutes of it and posted here:



Thanks again everyone!

I'd still love to be able to do the same thing to the Mega Drive version but maybe it's just not possible. If anyone has any ideas please let me know :)
PS SMS Power ENG 02.jpg (534.8 KB)
EPROM with SMS Power Phantasy Star
PS SMS Power ENG 02.jpg
PS SMS Power ENG 03.jpg (533.03 KB)
Yeah, a bit messy but I'm still learning!
PS SMS Power ENG 03.jpg

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Post Posted: Tue Jul 07, 2015 5:35 pm
TheSegaDude wrote
I'd still love to be able to do the same thing to the Mega Drive version but maybe it's just not possible. If anyone has any ideas please let me know :)


You would need to figure out a way of hooking one of those 315-5235 chips onto the MD cart PCB for it to work. The MD rom chip has a functional equivalent of the 315-5235 chip inside of the ROM and that's why putting a eprom straight on the board doesn't work.
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