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Pseudo Saturn Kai : still WIP ...

Written by cafealpha no comments
Still WIP, and last week was a busy one !

First, I fixed USB dev cart legacy firmware-like screen that wasn't working at all. Well that's a developer-oriented feature that I seldom use, but that needs to be fixed anyway
The fact I seldom use this feature was the starting point of the problem : modifying a module apparently not related with that feature caused major bug ... software development in a nutshell
Thank you Shazz for beta testing my firmware There are still other bugs remaining, and I plan to fix theses soon

And, (what's more important), game loader was sometimes loading game, sometimes not. Loading game backups is Pseudo Saturn Kai main feature, so I really don't want it to fail
Origin of this bug was unclear, but I fixed/improved many things at once, and game loaded every time after that, so let's hope I won't have to face with it in the future

One additional "bug" was game loader being kicked to multiplayer screen, and it was caused by ... game corrupted dump
First half of the game IP header was filled with zeros, so Saturn couldn't even recognize it as a Saturn game ...
I "fixed" what I could on firmware side by displaying something like "bad game dump/burn ?" message before kicking to multiplayer screen.
Let's hope it will reduce the amount of "can't load xyz game ! Hurry up to fix your bloody firmware !!" kind messages after release


And of course, there were many, many minor fixes, for example :
 - Added scrolling help messages under menus
 - Credits screen ... stub (names missing), and only in Save Data Manager for the moment
 - Added alternate menu exit keys : it is now possible to do something like "A/C:select, X:delete, Y:info, Z:whatever" in a single menu. This is preliminary work for Action Replay codes addition


So firmware development is continuing ! Everything is in good way :
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Pseudo Saturn Kai development is going well. Please disperse.
(Screenshot from The Naked Gun)

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Nothing to see here 
(Mr Nielsen, you're missing us )


On a positive note, I tested Bubble Bobble (listed as incompatible in Pseudo Saturn compatibility list), and it worked fine
I absolutely don't know why it works fine. I suppose that registers cleanup and running RAM cleanup code from ROM just before loading game helped a bit ... well at least it works



Completely unrelated note : I uploaded 10+ years old videos of me playing Tetris Attack puzzle mode ! You can enjoy the videos in my Tetris Attack page , or directly in the appropriate youtube playlist for theses videos.

data/images/20050105_ta_puzzle_ending.jpg
Tetris Attack puzzle mode ending screen

Read more Pseudo Saturn Kai : still WIP ...

WIP : Saturn Save Data Manager, Pseudo Saturn Kai & USB dev cart, etc

Written by cafealpha 6 comments
Pseudo Saturn Kai  firmware development is currently paused in order to focus development into Save Data Manager application

Saturn Save Data Manager is an application in order to manage (copy, delete, etc) save data on your Saturn.
Basically, it is similar to the save data manager provided by Saturn BIOS, but also offers extra things, such as multiple selection of items to copy/delete, GPL license, and also save data import from various formats.

data/images/20160125_bupmngr_main_screen.tb.png
Saturn Save Data Manager main screen running on emulator.
It also works on real hardware, but I was too lazy
 to take a picture of my TV screen


At first, this Save Data Manager was made only in order to test Virtual Memory Cart behavior, so maybe user interface looks a little cheap, but I plan to improve this in the future according to first users eventual feedback


I really want to thank two people whose work helped to make this application :
 - Rockin-B : for his good old SaveGameManager application (yes, I copied the name of the application).
 - hitomi2500 : for his ss-save-parser application that really helped to understand Saturn Save Data structure. Also, I merged its Save Import related sources to my project, so that copying save data from dump file is possible directly on Saturn too


And, there's one screen that I need to show from ss-save-parser application : the "extract options screen". This is image is worth a thousand words when trying to explain how save data is arranged in Saturn backup RAM

data/images/20160125_save_data_structure.png
THE screen everyone need to see before
hacking Saturn saves data
Save data is arranged as header
(containing save name, comment, etc),
then blocks allocation table,
then data itself, with header data at
the beginning of each blocks.




Extra #1 : last month, I took a video of USB dev cart in action !
Nothing really spectacular however, but please watch it if you want to see what developing application with USB dev cart looks like
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My dev laptop, a plain, not modded Saturn and USB dev cart,
ready for testing Saturn application on real hardware


Summary of the video (more details available in youtube page of the video) :
 - USB dev cart firmware update
 - CD-ROM unlock by using Pseudo Saturn hack
 - Upload and execution of program from PC to Saturn via USB, allowing testing of application performing CD-ROM access.


Extra #2 : with this USB dev cart, I could dump Shining Force Scenario 1 saves from Gosub .
You can find theses saves here.
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Backup cartridge with gosub's saves on it.
Thanks to Darius for providing me the cartridge

Gosub pushed each Shining Force character to their maximum competence on real hardware without using any cheat.
Really impressing work oO


Extra #3 : last month, my car reached its life achievement : 777777 kilometers :]
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Wow. Many lucky seven. So beauty
Next challenge : 777 777 kilometers !


Read more WIP : Saturn Save Data Manager, Pseudo Saturn Kai & USB dev cart, etc

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 :

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

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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

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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 !

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