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X-Terminator Cartridge Revival

Written by cafealpha 3 comments
This article is not about my own development experience, but from my friend XRider. Thanks a lot to him for the good work and the permission to share his pictures

First, what is a X-Terminator cartridge ? It is a Saturn flash cartridge which provides the following features :
 - 1MB expansion RAM
 - Backup memory
 - Ability to play import games
 - Cheat codes
 - Ability to search cheat codes by using standalone "X-Assist" unit

X-Terminator cartridge and X-Assist
Image taken from SegaRetro

X-Assist is particularly convenient because unlike Action Replay cartridges, it doesn't requires connection to a PC : it is true that connection to a PC provides more features (such as memory access, program upload, etc), but as "connection to PC" basically means "software support will be dropped someday", a standalone unit is a real treasure
For example, do you remember that Action Replay cartridges initially had DB25 connector ? This was for connecting the cartridge to PC via the -sold separately- Comms Link board, whose used now obsolete ISA port, and consequently not supported on nowadays PCs and/or OS.
There are some alternate solutions for connecting Action Replay to PC, whose major one is USB Data Link, but unfortunately it doesn't provides any software support for advanced features such as cheat codes search and testing.
So if you want to search cheat codes for your favorite game, X-Terminator is a good choice ! ... Okay, the user interface is in Japanese, but that's just a detail : after 200 or 300 hours learning about it, it shouldn't cause any problems

On the other hands, the major limitations are probably the lack of 4MB expansion RAM support, and using flash ROM for storing backup save data (which on the long term may brick the cartridge), but for a cartridge developed more than 20 years ago, theses limitations are quite honorable

So, once upon a time, XRider found a X-Terminator cartridge. It was a cheap auction, but on the other hand the cartridge didn't boot anymore, and the X-Assist unit wasn't included

Normal people would add this cartridge to their collection or put it on display as a decorating vintage objet Other people with engineering and electronics education background would put it on their "to repair someday" cardboard, and don't touch it for the next 20 years because they are busy with other projects or work, or real life, or all of theses at once

But XRider is none of them. XRider owns soldering tools. And knows how to use them. And really wants to fix this marvelous cartridge

So, let's try to fix the cartridge ! The first step would be to start with the most common problem, which is broken flash ROM.
In my opinion, this is the most difficult step, because it requires to desolder two chips for a total of 64 pins !
I personally can't do this because of lack of appropriate tools, so the alternate desoldering way I would had used would be to ... use a nipper and cut each pins

Fortunately, XRider likes work well done, so theses chips were removed in a clean way

X-Terminator cartridge, with flash ROM chips removed.
Additionally, all capacitors are removed too : that's
the occasion or never to replace them

Next step is a bit optional, and is about to dump removed flash ROM chips with flash ROM dumper device. This is the best way to verify if failure is due to corrupted flash ROM chips, and if still in working condition, this at least would be an occasion to dump the cartridge's firmware

Flash ROM chip on dumper device.

Dump is full of 0xFF bytes ... unless a miracle happens, theses flash ROM chips are no longer functioning  But, this comforts us regarding initial supposition of broken flash ROM chips causing cartridge not booting
Just in case of, let's verify PCB traces around flash ROM chips while theses are removed : this takes only 5 minutes to check, and it would be frustrating to find that cartridge was not working because of broken trace after soldering new flash ROM chips

PCB traces : just requires a light source
strong enough to be seen

What to do next ? Maybe use PLCC sockets so that future replacement of flash ROM chips would be easier ! That's a couple of weeks to wait for the postman, but worth the wait
PCB with PLCC32 sockets soldered

And then, simply replace the flash ROM chips

Next generation is here !

PCB with new flash ROM chips.
Additionally, new capacitors are populated

One last step remaining ! Flash ROM is mounted, but ROM itself needs to be set up with X-Terminator firmware. The simplest way to do this is to use Pseudo Saturn Kai flasher utility : it obviously allows to install Pseudo Saturn Kai, but also several other legacy firmwares in the case someone would want to revert to initial firmware after trying Pseudo Saturn Kai.

Just select the ROM version you want to install,
and follow on-screen instructions

Flashing in progress ! Will it work after that ?!

Yeehaw !!! It boot fine, mission done
Let's try with Metal Slug ...

Metal Slug works too !
So it seems there's no need to replace RAM chips

Everything finished ? No, there is a side quest remaining Among the couple of X-Terminator cartridges XRider owns, one X-Assist (pad and LCD unit used to search cheat codes) is missing.
One X-Assist available ? And another one missing ? No problem : let's reverse engineer the first one and DIY the second one

The X-Assist features two PCBs : one for connection interfacing and pad, and another one for LCD, as pictured below.

X-Assist pad/interfacing board

X-Assist LCD board

The LCD board is incredibly complex, but since it was manufactured as a whole and can still be purchased on auctions or second-hand market nowadays, there's no real interest to build it from scratch ! And I personally wouldn't try : that seems too much complex

So remaining is pad and interfacing board : fortunately it uses standard components and not any Gate Array Logic-ish components that would need to be reverse-engineered too. Simply speaking, it's like assembling LEGOs
Multi-meter, a LCD board, electronic breadboard, a bunch of wires, few electronic components ... is there something missing ? Yes ! A LOT of motivation !!

X-Assist DIY prototype, in all its glory

It's so beautiful it deserves another picture !

Let's try for real ! Of course, after verifying any eventual short-circuit with a multi-meter 
No short-circuit ? It's then ready for the "first-lighting ceremony" (火入れ式), as it is nicknamed in my neighboring ... I don't know if that's a common expression in Japan or anywhere else, but I like its naming anyway

No sparks ? No smoke ? That looks good

At first glance, that seems working ! Let's try cheat codes search feature in order to be 100% sure ...

Search unit not found ?!

Arg, it was too early to sing victory X-Assist seems not being correctly detected by X-Terminator cartridge ...
Since text could be sent to the LCD, let's assume nearly everything is working correctly, and that a small detail is causing this trouble ... after some head-scratching, XRider found what's wrong : a Zener diode that initially looked useless was used to return some ACK to X-Terminator cartridge when looking for its connection !

The X-Assist screen after adding the Zener diode :
code search memory could be captured !

65535 candidate codes ?! I'm not sure if correct cheat code could be found this time, but at least the DIY X-Assist unit works correctly now


Additional informations are available in French  on Darius forums :

Credits :
 - XRider, for the good work in game cartridges preservation
 - Darius, for gathering French community around Saturn

Read more X-Terminator Cartridge Revival

Pseudo Saturn FAQ, May 2017 edition

Written by cafealpha 6 comments
Here is a small FAQ about Pseudo Saturn, so that it may help people experiencing troubles when installing or using Pseudo Saturn, and also ... reduce the number of inquiries in my mailbox

Pseudo Saturn 0.832 "Booting CD ... Error 1" message when trying to load a game.

The "Booting CD ... Error 1" message.
Special Thanks to C.L. for reporting the problem and sending the picture

This problem happens with Pseudo Saturn 0.832, both "no logo" initial build and final release with classy logo.

It concerns :
 - A specific hardware revision of Saturn : Japanese grey model 1 (95% sure), with power supply connector screwed to Saturn top case (not so sure).
 - Any game or application on burned on CD-R

So if you have Pseudo Saturn 0.832 and the "wrong" (incompatible) hardware revision of Saturn, it's not possible to play any CD-R copy of your games, and consequently can't upgrade your cartridge to other version of Pseudo Saturn, since it requires to boot a CD-R

Annoying isn't it ? The countermeasure is to either :
 1. Install latest Pseudo Saturn Kai on your Saturn cartridge
 2. Use another Saturn, compatible with Pseudo Saturn 0.832 :
      - Model 2 Saturns are 99% safe : I didn't received any "Boot Error 1" report with model 2 Saturn.
      - Please try on another model 1 Saturn only if you were lucky that day, else please be sure that this other Saturn won't be compatible too

Owning a spare and compatible Saturn -or being friend with somebody owning one- is the best solution, since it allows to both upgrade to Pseudo Saturn Kai, and to play games compatible with "JHL (PS 0.832)" game loader.

Owning only 0.832 incompatible Saturn(s) will bring you to "install Pseudo Saturn Kai on a bare Saturn" step, so basically requires to open your Saturn, watch swap trick tutorials on youtube, fail several times in trying that ('%)=(&$ swap trick, finally success in installing Pseudo Saturn Kai , look for one missing screw in order to put back Saturn top cover, re-open the Saturn in order to remove the tape on CD-ROM lid open switch, and finally put back the Saturn in its original condition

Long install steps ? Yes, but at the end the problem will be fixed (if not, please contact me)
However, there's a limitation when using Pseudo Saturn Kai on model 1 incompatible Saturns : the few games not compatible with Pseudo Saturn 0.831 won't be playable
Incompatible games are the ones marked as requiring Pseudo Saturn patcher utility, in Pseudo Saturn Kai compatibility list. Notable examples are Panzer Dragoon Saga, Batman Forever and Alien Trilogy.

You sold a kidney in order to buy original discs of Panzer Dragoon Saga, and really want to play their CD-R copies on your model 1 Japanese Saturn so that original discs won't be damaged ?

Except selling the remaining kidney in order to buy a Rhea/Phoebe (), the only solution is to wait until a new version of Pseudo Saturn Kai is released, and hope I find a fix to this problem.
While waiting for new version of Pseudo Saturn Kai, how about trying games that Pseudo Saturn Kai can play with its good old "CWX (PS 0.831)" game loader ? I would for example recommend NiGHTS into dreams, Shining Force 3 series, and also Virtua Fighter Kids

"Firmware file read error !" message when trying to install Pseudo Saturn Kai

"Firmware file read error !" message (hard to read, sorry).
Grabbed from reddit, special thanks to yoqu for reporting the problem

First, I fixed error text display in Pseudo Saturn Kai's latest release (v6.074) : it is now displayed with white background color. Readability varies from a TV monitor to another, so please contact me if that's still not readable on your TV

This problem is generally caused by incorrect timing when performing swap trick, which makes Saturn booting Save Data Manager and Flasher utility from CD-R, but not being able to read files from CD-R after that.
Another causes may be Saturn's laser incorrect calibration, or affinity problem between Saturn CD block and CD-R brand, or burn settings.

The countermeasure is simple : please use Pseudo Saturn Kai alternate flasher utility, located in Pseudo Saturn Kai latest archive → pskai_alternate_flasher.iso. This requires another CD-R, but this will work
And, burning Pseudo Saturn Kai Save Data Manager and Flasher utility (pskai_sdm_flasher.iso) wasn't a waste, since it will boot correctly after flashing your cartridge to Pseudo Saturn Kai. Save Data Manager contains many save data to import to your Saturn, so you probably want to use them in order to start playing your favorite game elsewhere than level 1

So, what's the magic behind Pseudo Saturn Kai alternate flasher utility ? nothing really special in fact : both flasher executable and Pseudo Saturn Kai firmware data are packed in a single Saturn executable file. So as firmware data is loaded just after performing swap trick, file read error won't happen

Definitely not a smart way to counter a problem,
but it works, which is the most important

This "alternate" flasher utility was developed before Pseudo Saturn Kai, and used in Pseudo Saturn 0.83x flasher utilities. I then developed an "all in one" Save Data Manager & Flasher utility on a single CD-ROM which allows to flash cartridge, manage save data, etc.

I though this would make the "alternate" initial flasher utility obsolete, so that it was dropped in Pseudo Saturn Kai 6.036 and 6.037 releases ... unfortunately I was reported about that "Firmware file read error !" problem after that
So as a countermeasure, I restored this utility from Pseudo Saturn 6.074. Sorry for the troubles caused

Additionally, some more informations about this problem are displayed in current (W.I.P.) Pseudo Saturn Kai version.

Updated error message in flasher utility.

Pseudo Saturn Kai development continues ! Stay tuned

Read more Pseudo Saturn FAQ, May 2017 edition

New USB dev carts for sale !

Written by cafealpha 6 comments
Last week, I soldered new USB dev carts, so please let me know if you want to purchase one

What's new with theses carts ?
I use new PCB (Rev 2e) and flash chips that allow to store firmware larger that Action Replay firmware :
 - Action Replay Flash ROM : 256KB
 - USB dev cart Flash ROM : 512KB
It will be useful when making custom firmware for this cartridge

And, I'm now familiar with using flux when soldering ! Before, I was soldering small pitched parts (typically, the FTDI USB chip) with stain in excess, then using solder wick. This gave good results, but I wasn't satisfied with the visual aspect nearby soldering points :

Before : only stain & solder wick used to solder FTDI chip

After : flux used to solder FTDI chip

And, there are now "ROM cartridge" available for sale !
This is just an "USB-less USB dev cart", but it allows to run Pseudo Saturn firmware, and also future revisions of the firmware with ROM size larger than 256KB available on Action Replay carts. And of course, it is a little cheaper than USB dev cart

ROM cartridge ... well, this is just USB dev cart without USB modules, so nothing really new ^^;
This cartridge is interesting in the case you want an USB dev cart for dev things, and another cart for gaming purpose.

Read more New USB dev carts for sale !

Treatment report (2014/08/12)

Written by cafealpha no comments
Nothing really special today.
This morning, the roommate in front of me (separated by 2 curtains) left hospital, so I am now the patient with the longest stay in this room.
Previous roommate always spoke to himself while sleeping, so it's great that he finally left hospital

Among the two roommates remaining with me in this hospital room,
 - first one snores loudly ...
 - second one likes to play with room's air conditioner settings ... I don't know why he set temperature room to 28℃ .... maybe a game with me, I don't know.
Anyway, I plan to restore temperature to 26℃ as soon he changes it ... I have no choice, because his favorite temperature feels like hell to me.
And if he really continues to bother me, I will pour extra strong bond on air conditioner remote controller buttons

Doctor now use small syringe to pour sterilized solution in my mouth's scar in order to clean it, which is a sign that everything is going well for it
Also, according to the doctor, there's no longer need to clean this scar twice a day : once a day is now enough, which is another good sign about this scar :]
I hope this scar will close properly this week. After that, I finally will be able to start eating rehabilitation !!

On Saturn dev side (at first, this blog was intended to be a Saturn dev related blog !), I had fun with interrupt C and code executing on ROM ... except constant ones (of course), no global variable is allowed for ROM code ! Ouch.
Still not compiling, less than half of the project is coded, nothing tested, so I will continue tomorrow

Read more Treatment report (2014/08/12)

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