PPcenter donation system updated !

Written by cafealpha 4 comments
More than 11 years ago (from winter 2005 ?), I had a "donate" page stating something like "send your money and I will make cool things for Saturn on my free time".

During there 11 years, I received 15 US dollars.

And within theses 15 US dollars, I declined 10 because they were generously donated in exchange of "future help" in making a game for Saturn.

So that's something like 45 cents per year, which is also around 3.8 cents per month. I didn't checked in details, but that should be something like one Skittles per week. Not one bag of Skittles, but one bloody skittles. Per. Week

Fortunately, this era now ends, because I officially announce that I changed my donation system from "send your money and I will make cool things for Saturn on my free time" to "Send everything except money, and I will make cool things for Saturn on my free time. And even if you don't donate anything, I will make cool things for Saturn on my free time anyway."
More details can be found on my donate page

And to make it clear : the motivation to change donation system is not related to money : I just spoke about money received so far in order to write something funny in my blog

I make Saturn things for fun, and not for money. As some examples, I started to design rev2f PCB in hospital room from one week after undergoing cancer surgery, and Virtual Memory Cartridge add-on for Pseudo Saturn Kai was developed and tested during my post surgery chemotherapy. Theses helped a lot to think about something else than medical things during theses times.
I don't say that Kicad and gcc are a cure for cancer (), but theses were very good help however.


And to make it clearer : yes, I sell Saturn cartridges, but no I don't make a living from selling theses. I'm not even sure I produce enough carts in order to pay every-day's breakfast from cartridges sales benefits

Read more PPcenter donation system updated !

Bit shift in Saturn minimalistic C program

Written by cafealpha 4 comments
While making a Saturn program running directly from ROM, constraint is usually to have program as small as possible. Why ? Because I would like to make Pseudo Saturn Kai continue supporting Action Replay, which have limited ROM size

So, in that situation, I use homemade, minimalistic stdlib, containing usually only memcpy and memset functions, and everything goes well.
But for some reason, current program was begging for __ashlsi3 and __ashrsi3 functions.
... What's these things ? __ashlsi3 is an assembly function doing left shifts of data, and as you probably guessed, __ashrsi3 does the same, but with right shifts

No problem, let's ask my friend google, and copy & paste theses functions without minding about their contents Theses functions are standard functions provided by C library, so sources can be found here and there.


An example of what __ashrsi3 function looks like

A day after that, here comes the time to do basic testing of this ROM code
Let's first start with simple things such as screen display ...


Text display ... not as expected ?!

Hrm, it's probably a problem in my printchar routine ?

printchar source code : this is the core thing
behind text display in my programs

But that's a very long time I didn't touched this routine, which works well on Pseudo Saturn Kai, and works even better in vdp1ex from Charles MacDonald sample programs, because all my printchar routines come from there
But just in case of, let's try to tune one " <<3 " into " *8 " in the code above, and see if that changes something. Theses two operations are equivalent, so this should give the same result, but ... Saturn screen becomes all black

Okay, there's definitely something weird regarding that printchar, but I just re-used it as-is from other project, so what's going wrong with my it ?!
[...]
And then (finally) a light-bulb above my head appears Maybe there's something wrong regarding the __ashlsi3 and __ashrsi3 routines ?
And, yes there was something wrong regarding theses routines ... I wrote a paragraph about them on the first half of this article, so it would be surprising the problem came from somewhere else

In more accurate words, routines are OK, which is normal since they are written by people smarter than me But the calling convention of __ashrsi3 was not as my gcc was expecting ?
Well, that's just a guess from the display results, because it seems to display the same pixel 8 times on each row of a given character, which may happen when ignoring shift parameter in __ashrsi3 function.

Anyway, rather than finding in details what's wrong, let's fix the problem First, with assembly by hand, in desperately trying to change input parameter handling ... I don't remember exactly what I wrote, but that was something like pushing a register to stack, moving parameter to it, finally restoring register, putting nop instructions everywhere, etc ... nothing difficult, but over my extent in assembly programming

The result is ... a mixed success :

Trying to modify __ashrsi3 routine by hand ... well, it seems that
some shift values are not correctly handled

Okay, so let's re-ask google about that __ashrsi3 routine ... and a different implementation arrives in search results. Let's try it


__ashrsi3

And the execution result :

Execution result with second version of __ashrsi3 function

Yeah, it works this time !!! And don't ask me why, because I didn't took time in understanding what's different in that second version of __ashrsi3 function
And, rather than understanding why it works ... let's close that assembly pandora box before some other mystic bugs pop from it

I will probably see about this in the future, but that was absolutely out of the scope of today's programming, and in software world, too much digression leads to freeze of projects, which I would like to avoid in order to go forward to next pending project 

As a example, I started to adapt yeti3d engine to Saturn in 2010 (7 years ago !), and this ended in ... developing a SD card based memory cartridge for Saturn !
The point above is is not a joke : menus used in my yeti3d adaptation are the origin of menus used in Pseudo Saturn Kai, which shows the continuity (co-consanguinity ? ) in my projects. And after getting yeti3d working a bit, I really would like to load levels from something else than CD-ROM, which was from PC (via adequate link cable) on a first time, and which will (should ?) then evolve to SD card.
That would be cool to make a Saturn game not requiring to burn CD-ROM somedays, but before that I need to finish neighboring side quests


Evolution of my Saturn projects

To conclude this article, let's say it was terribly fun to see some bits of the internals behind C language
By the past, I remember I did something similar with my yeti3d adaptation, but remained at "C language level" : optimization done at that time was (IIRC, ) to avoid 4 bits shifts, because theses are not available in a single SH-2 CPU instruction. Avoiding 4 bits shifts was simply done by merging two fixed point operation in a single one (or something like that : I did this 7 years ago !), and this actually gave some improvements in 3D scene rendering Theses were the good times ... I sometimes think "I'm Getting Too Old For This Shit", but that's only to motivate to finish my old projects

But before that, Pseudo Saturn Kai, and then Kicad and Quartus are waiting for me


BTW, in the case you wondered about what was today's programming session, you probably guessed it was about exception handler addition to Pseudo Saturn Kai. This not a new feature, since it was available in Pseudo Saturn 0.83x ... in fact, I grabbed some sources from Pseudo Saturn 0.83x in order to implement this exception handler (thank you CyberWarriorX !) This exception handler will be available as a small add-don to cheat codes feature in Pseudo Saturn Kai next major release.

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Similar looking kanji definitions file update

Written by cafealpha no comments
Classified in : Programming, Mylife Tags : japanese, JWPce, update, homebrew
It's been a while I didn't received an email not related to Saturn from my homepage, so I was quite happy when siikamiika asked me if he could safely license similar kanjis definition file in MIT licence in his similar-kanji project


What is "similar kanjis definition file" ? It is a text file used in "My JWPce" which defines ... kanjis looking similar
The original idea about this is not from me : I initially found this feature in kanji.free.fr (Japanese → Omelette du fromage online kanji dictionary), and thought it would be cool if this feature could be available directly from my favorite Japanese electronic dictionary.
So I build this "similar kanjis definition file", and added support for it in "My JWPce".

data/images/20170220_jpwce_similar_kanjis.tb.png
Example of in JWPce's kanji information
dialog : "似" looks like "以", "代" and "伐"

If you're Japanese, or were learning Chinese characters from elementary school, this definition file is probably a complete nonsense for you, since you know how to enter the correct kanji from keyboard on first try.
But that's not the same done for foreigners who started to learn Japanese in their twenties, so that this feature helped me a lot when learning new kanjis :
 1. In JWPce, enter a kanji similar the new one you can't read
 2. Search for that new kanji in similar kanjis list
 3. ????
 4. Profit !

So of course, MIT licensing of this file is OK, and I was also glad to overwrite my old definition file with siikamiika's version, so that I could enjoy all new entries added in this version
Open source is love, open source is life, thank you siikamiika

Read more Similar looking kanji definitions file update

Gamer's Cartridges temporarily not available ! (Edit: now available ♪)

Written by cafealpha 10 comments
Classified in : PPCenter, Saturn, Mylife Tags : vacation, mylife, Christmas
Normal sales people make announcements when their things to sale are available ... I personally don't like aggressive advertisement, hence prefer to make announcement when things to sale are not available

So I don't plan to process Gamer's Cartridge for a while ... reason for this is simple : I can't go to post office during winter vacations (and probably won't have time for emails too), so I prefer to temporarily stop selling cartridge rather than asking people for waiting

data/images/20160612_gamers.jpg
Sorry, that's the only picture I found for this article
(Grabbed from here )

So I wish you nice winter vacations ! I don't know there, but weather here is cold and windy, hence well suited for playing Saturn


Edit (2017/01/12) : cartridges are back for sale ! More informations on my Saturn cartridges page.
During winter vacations, I found a couple of cartridges with "Rev 3.3 (a)" PCB (one revision before latest revision, only position of LEDs is different) while tidying up my apartment
BTW, happy new year

Read more Gamer's Cartridges temporarily not available ! (Edit: now available ♪)

Recovered from "cold" :)

Written by cafealpha 2 comments
Classified in : etc, Mylife Tags : mylife, treatment
I actually recovered a long time ago, but didn't had enough free time to write a new article until now
So I totally recovered from my pneumonia ... "Klaricid" helped me a lot to get rid about it. Many thanks to the doctors and many other people who helped me in theses hard times
Winter is coming, but I'm ready to face it

On a related note, I had a day trip to hospital last month for my cancer screening, and according to CT scan and blood analysis, everything is OK
data/images/20161121_no_pokemon_go_in_hospital.jpg
"Smartphone game Pokemon GO forbidden in hospital"
From : director of the hospital


Work is keeping me busy recently, and that won't change until summer, but I keep doing Saturn stuff doing my spare time

Read more Recovered from "cold" :)

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