project sd2snes

KRIKzz has opened sd2snes pre-orders!

ikari — Thu, 19 Apr 2012 14:55:28 +0000

KRIKzz has opened pre-orders for his production of sd2snes!
Pre-orders can be placed now at retrogate.com.
This also means they will appear at Stone Age Gamer shortly.
As far as I know, gp2x.de is planning to carry them as well, so stay tuned.

Firmware v0.1.3

ikari — Wed, 29 Feb 2012 22:26:48 +0000

Firmware v0.1.3 is out with these changes:

Updated logo gfx with final version from klaptra
Updated font to distinguish between 1 and I
Menu layout adjusted to move status line up by 4 scanlines
Run previously loaded game by pressing Start in the menu
Auto-scroll file names that do not fit the screen
SD access time measurement on System Information screen (takes a while!)
Cx4 memory map: mirror ROM to 40-7d/c0-ff (fixes MMX3 fully playable Zero patch)
Fix: FPGA-side SD clock pullup (increases reliability with some cards)

Download it here.

sd2snes – available soon from KRIKzz!

ikari — Sun, 15 Jan 2012 16:55:09 +0000

I guess I’m a bit behind the rumors already
sd2snes will be available soon from KRIKzz. The first stores to sell them are Stone Age Gamer and Retrogate.
http://www.assemblergames.com/forums/showthread.php?t=37008

I’m asking everyone on the 2012 pre-order list (who got a confirmation) to contact me whether you would like to stay on the list or order from one of the stores. Honestly I really encourage you to do the latter because it gives me more time for actual development.

Firmware v0.1.2

ikari — Sun, 15 Jan 2012 16:43:43 +0000

Firmware v0.1.2 is out with these changes:

Auto region override (eliminate “This game pak is not designed…” messages)
Improved mapper detection (fixes some games and many PD ROMs)
Improved data streaming performance (should reduce MSU1 errors with some cards)
A and B buttons swapped in menu to match common key mappings
Fix: MSU1: Stop audio playback at end of audio file

Download it here.

Cx4 finished

ikari — Sun, 06 Nov 2011 13:24:43 +0000

The Cx4 FPGA core is complete. Check it out:

Status page added

ikari — Sat, 05 Nov 2011 09:24:27 +0000

I added a status page to reflect the current status, feature set, and progress of the project.

Baby Steps…

ikari — Sun, 16 Oct 2011 20:47:45 +0000

Cx4 first progress

Cx4 memory map and data RAM are implemented. No work done on the actual core yet. Still, sometimes it’s nice to get any positive feedback from the hardware.

Prototype – assembled

ikari — Sun, 16 Oct 2011 20:40:32 +0000

I had the Rev.E proto assembled by the end of August – but never got around to showing it off.
Well, here it is.

Rev.E front, assembled

The fat 4MBit SRAM at the top isn’t used yet. Its purpose is to retain save data in case of power failure (before it’s written to SD card), to serve as custom chip work RAM, and probably to store some other status information. Save data is currently stored in PSRAM along with the ROM, and monitored/saved to card from there.

Rev.E back, assembled

Though the Zeroplus Logic Cube is rather low-end, it’s still a 200MHz, 128kSamples LA that has proven invaluable for all sorts of debugging. The JTAG/UART adapter (not shown) is a run-of-the-mill FT2232 DIP adapter board which plays nicely with OpenOCD. This one I got cheap from Akihabara (thanks to Tobias Diedrich!).

Rev.E in operation, wired up

Latest prototype PCBs arrived

ikari — Thu, 11 Aug 2011 03:20:23 +0000

Quick update, the latest prototype PCBs arrived a couple of days ago. Assembly is in progress. This revision reduces audio noise from the DAC. This was a problem with 1CHIP SNESes which introduce much more noise, presumably due to their much steeper signal edges on the bus. The noise disappears when using a “custom chip game” case with the additional grounding prongs. I didn’t want to rely on that though, hence the hardware update.

Here they are. I hope this is the last hardware revision, all those prototype PCBs are getting expensive…

sd2snes Mk.II Rev. E, front

sd2snes Mk.II Rev. E, back

1CHIP SNES picture quality – quick comparison

ikari — Mon, 01 Aug 2011 20:26:47 +0000

I did this a while ago and thought it might be interesting. The 1CHIP SNES (1995~), with S-CPU, S-PPU1 and S-PPU2 united in a single chip (S-CPUN), has vastly improved picture quality over the old versions. Most notably the rising edges of the output signal are much steeper, resulting in sharper dark->bright transitions.
This is not an issue of the video encoder, it looks exactly the same via RGB (save for color balance).
Here are some examples to show the difference.
Sorry the pictures turned out quite big but it’s important not to lose any detail here.
The images below show three frame captures from a “regular” SNES. Roll over them to see the 1CHIP version.

Shot 1

Shot 2

Shot 3