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PPcenter. Arts and craft for my Sega Saturn. Since 1847 :D

Just moved !

Written by cafealpha 4 comments
During the last weeks, I was busy in preparing stuff in order to move to a new apartment.
And now, I am busy in ordering stuff in this new apartment ^^;

data/images/20141129_gaston.tb.jpg
(Image of me preparing cardboard few hours before mover truck arrives)

During the next weeks/months, I don't plan to do some new Saturn stuff. Instead, I plan to do things related to my new apartment, like emptying cardboards, ordering rooms, selling old/unused things, etc.
By the way, I plan to sell old Saturn games from my collection, including PAL Panzer Dragoon Saga, Shining Force III Scenario 1, so please let me know (= add a comment to this article, or send me a message) if you want to purchase something :)
In the case things are sold directly from this homepage, it will be cheaper than in the case I sell them via ebay ;)

PS : I didn't set up internet connection in my new apartment, so I may not be able to answer mail/messages/whatever during the next couple of weeks.

PPS : happy birthday Saturn ! It turned 20 years old on last month ♪

Read more Just moved !

New USB dev cart - currently debugging

Written by cafealpha 4 comments
Few weeks ago, I had some free time (only one day however) to populate new USB dev carts
data/images/20140829_usb_dev_cart.tb.jpg
USB dev carts during different populating states
"This isn't even my final form"

I could populate 3 boards ... third one is not on the picture, while a couple of capacitors is missing on second one, but this is a matter of 5 minutes to solder.
After that, time was missing, and what's more problematic, ICs were missing too >_<

I soldered my last flash chips (on the right side of the cart), as well as my last USB chips and connectors (top left side of the cart) ... and my last 100nF decoupling capacitor (everywhere near all ICs) too ... it's a shame about the capacitors because they cost absolutely nothing and they are required everywhere in the cart.

So what's the plan from now ? I'm currently improving USB dev cart firmware, and plan to sell the completed cartridge on the bottom right corner of the picture when firmware will be ready for release.
From that money, I will buy a new stock of ICs to populate other PCBs
Why not buying ICs now ? Simply because I don't have enough budget for that, and also because buying ICs in few quantities is too much expensive : IC price decrease with quantity, and shipping fees are free when more than of USD100 of ICs are purchased.


So let's come the interesting part : firmware, which means software !
Last month I had enough about PCB design with Kicad, so that was good to get back with my Saturn and USB connect it to my laptop

data/images/20140829_dev_env.tb.jpg
My Saturn development environment : no expensive vintage development kit,
only a modchipped Saturn, USB dev cart and 7 years old laptop are enough.

So of course I lost a lot of time with stupid software troubles.
Here is a list of the troubles. I hope that writing them here will prevent me from repeating the same mistakes in the future.

 1) Data alignment problem : one structure is 1 byte packed, and some long word was put a non 4 multiple offset in this structure. It is usually easy to spot, but ...
 - It doesn't cause problem under yabause (? not verified, please tell me if I'm wrong), so this problem was unnoticed until I test it under real hardware.
 - It happened during program initialization, before USB transfer would allow me to easily find why my Saturn freezes.
 - I was sleepy at this time

 2) Adding byte size to unsigned long* pointer ... it resulted in pointer set 4 times farther than expected ... really stupid bug
Oh, and in the same fashion, a similar bug in Action Replay flasher utility prevented from writing more than half of flash memory size ... it's good that I could fix this bug before anybody notice it

 3) Saturn freezes when reading flash vendor/device IDs.
As usual, when Saturn freezes, it is during program startup, when USB can't be used for debug ^^;
This problem was the most interesting one : some parts of the firmware runs directly from Flash ROM, and it seems that reading flash vendor/device IDs makes whole flash returning theses IDs, resulting in invalid instruction from CPU ... this is just a guess, correct me if I'm wrong.
This problem was corrected in a very Q&D way : return 0xBFBF/0xB7B7 in FlashGetVendorID/FlashGetDeviceID functions
I have a better idea to fix this, but it requires to modify cartridge flasher utility ... I made enough flasher utility stuff recently (I'm enough in fixing compatibility issues with Action Replay old flash chips !), so I will fix this later.

Read more New USB dev cart - currently debugging

Saturn cartridge firmware flash utility : small update #2

Written by cafealpha 12 comments
I made some fixes to my flasher utility.
 - Added support for SST29LE010 flash chip
 - Added memory verify after flashing
 - Fixed erase/write operations AM29F010 flash chip
 - On startup, inform user that 3D pad and multitap pad are not supported

Thanks to beta testers on ASSEMbler forums, this new version has high chances to work on your Saturn cartridge
However, if you experience any problem, please let me know by leaving a comment to this article.

Some screenshots :
data/images/20140829_bfbf_0808.tb.jpg
BFBF/0808 flash chip, not recognized on previous version.
This version does now detect it as a 29LE010 device from SST.
Picture provided by dgist71.

data/images/20140901_flash_ok.tb.jpg
Write to AM29F010 chip was incorrect in previous version.
As displayed in this screenshot, this is fixed now.
Picture provided by XeCuTioNR.

You can download this utility here : flasher_20140902.7zflasher_arp_20150326.7zhttp://ppcenter.webou.net/pskai/
Disclaimer : You will loose your cartridge backup data after reflash. And, I'm not responsible in the case I brick your cartridge and/or damage your Saturn.

Read more Saturn cartridge firmware flash utility : small update #2

Saturn cartridge firmware flash utility : small update

Written by cafealpha 17 comments
Memory Card Plus restore utility I made few days ago is now obsolete : I added a menu to select the firmware to flash.
Firmware list includes Action Replay Plus/Pro (various versions), latest Pseudo Saturn, Memory Card Plus, USB dev cart.
data/images/20140821_flasher_fwlist.png
Firmware selection menu

As you can see, I added some colors in text display too

The utility doesn't read data from the CDROM, so that it can be uploaded to Saturn via commlinks port (Action Replay) or USB port (USB dev cart).
All the firmwares don't fit as-is in Saturn HRAM (1MB), so I compressed them by using LZF compression, so that everything could fit in a single ~800 KB binary file

Here are some pictures of utility running on real hardware :
data/images/20140821_flasher.tb.jpg
Firmware selection menu from early beta version.
Picture provided by r1cola.

data/images/20140824_flasher_video.png
(click to open video)
Flasher in action : from firmware selection to end of flash operation.
Video provided by zorlon.

You can download this utility here : flasher_20140824.7zflasher_20140902.7zflasher_arp_20150326.7zhttp://ppcenter.webou.net/pskai/
Disclaimer : You will loose your cartridge backup data after reflash. And, I'm not responsible in the case I brick your cartridge and/or damage your Saturn.

Read more Saturn cartridge firmware flash utility : small update

Back home !

Written by cafealpha no comments
Home sweet home !
There's no more hospital staff to prepare food or take care of my scars, shampoo, whatever, but returning back at home after around 6 weeks at hospital is nice

Today, I could get my hands on ICs for USB dev cart and Saturn dev stuff (Saturn, small TV, damaged proto carts, etc) that I put in a small storehouse before entering hospital.
Everything is still in cardboards/bags ... I shall tidy the apartment a little before to do some Saturn things ^^
Oh, and I finally could touch the new PCBs I ordered 3 weeks ago

Read more Back home !

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