Well that’s stupid

I received a few reports that Stupid Invaders, both EU and USA region versions, doesn’t work on GDEMU. It took a whole evening but I figured out what hangs it. I still have no idea why though. The “solution” for now would be to break an otherwise functional piece of code, which is simply unacceptable – so the actual issue must be something else. Perhaps it’s another timing problem, maybe GDEMU is returning data too fast and that confuses the game. It is Ubisoft title after all…

I’m going to investigate further, if I can’t find a proper solution soon I can always do that dirty fix. It shouldn’t affect other games, it’s not exactly a core functionality that needs to be changed.

In other news: Seems like US Postal Service gave me the middle finger – they no longer track my shipments. It might be a system glitch as they don’t show tracking for the codes that worked earlier, but the result is the same nonetheless – it’s broken, has been for days now, and doesn’t look like it’s going to be fixed soon.

On the bright side Australian post decided to stop being the odd one and now they do track international registered mail it seems. Or maybe it’s some sort of baton that got passed to USA now. Well done, except you could’ve picked somewhat less frequent shipping target maybe?


A new FW for GDEMU is now available, get it in the UPDATING FIRMWARE section. The changelog might not reflect that but there are many internal changes, most of the code is now shared with Rhea – this will save me some work in future.

I didn’t have time to test it as well as I would like so just in case I left a link to 5.7.0 in the changelog (should anyone need to downgrade).

Folder limit is now set to 9999, but to avoid having to rename everything it works like this:

  • for 1-9 put 0 in front to make it 01-09 (*)
  • for 10-99 use 2 digits (*)
  • for 100-999 use 3 digits
  • for 1000+ use 4 digits

(*) – same as it was until now

Simple, right? There is no folder prescan anymore so you can’t have gaps in numbering. Also, DOWN key (for those that have it) will now stop at 1 instead of wrapping around to the highest available image. The official maximum SD card size is still 32GB, so don’t bother me with reports of anything bigger not working right. You will be ignored.

SD high speed mode is an experimental feature. While it does double the card transfer rate, that alone has little impact on Dreamcast games – most will be limited by their own internal processing anyway. It will not work well, if at all, with extenders, and not all cards will behave properly – therefore it’s disabled by default. It’s mostly for people with problematic Class 10 cards, might just make them work. Do not report issues with high speed mode enabled.

EDIT: Seems I broke the button API needed by menu software, sorry for that. 5.8.1 is up and should have it fixed.

Cold is here

And by cold I mean both weather and the fact that I got sick. That has seriously slowed down GDEMU assembly so I’m running a bit behind schedule now.

There’s another problem as well – my primary supplier has run out of FPGAs I use and the next delivery will happen in December (if there are no more delays). It’s important because they got them considerably cheaper than other sources (Farnell, Mouser, etc) so I can’t just order those somewhere else without raising GDEMU price. Well, truth be told I did order some anyway, to fill the gap a bit, I’m going to cover the price difference myself – but that’s not a viable long term solution.

On the bright side I did manage to finish and test the ARM7 replacement I wrote about earlier, this is how it compares:


The new chips is what, 3x faster than the old one? Plus I got rid of the serial Flash on the other side, I never used that anyway and it only permanently tied one I/O for chip select signal. One more step towards PCE prototype.

Somewhat interesting trivia: Atmel named most of their ARM MCU family “SAMx” where x is a digit, 7 for ARM7, 3 for Cortex-M3 and 4 for Cortex-M4. Now that ARM has came up with a new Cortex-M core, and decided to call it M7 rather than M5, I wonder what Atmel will do 🙂

Oh, and this might also interest some of you, RheaV2:

RheaV2 - installed

Does it work? Well, do bears shit in the woods?

After a few tweaks to the PCB layout I’m going to try and sell some 20-30 units, if at all possible, to interested parties. For now I’d like to run some more tests to make sure this device works as intended, this will take time though. A few weeks probably. However I might be persuaded to sell something before I finish testing, provided that you fully understand you’re buying a cat in a bag. Or a pig in a poke for you English speakers.

So, to sum this up, this is just 20-pin drive emulator for now. It hasn’t been tested much with all the changes from V1 (most importantly, a different MCU). I still have to make sure you can pair it up with later models using a single piece of flat cable, as SEGA seems to have reversed the connector orientation on the mainboard for some reason. It would be best to use a connector with contacts on 2 sides for that very reason but good luck finding that on sale, at reasonable price. I’d prefer to use ZIF connectors but these are always top or bottom side contacts. It will most likely require you to solder 1-2 wires for 5V power supply. And the very first units are probably going to be more expensive due to small batch. But you might just get a fancy Xmas gift 😛

Anyway, if you’re feeling lucky, drop me a mail. Expect ~130 Euro quote. Serious offers only for now, my head is killing me and I’m really not in the mood for “maybes”.

Xmas gift factory

As some of you already noticed preorders for GDEMU are open again. I did it quietly this time to not have my mailbox overloaded. I still have more units coming but be aware that the waiting time is already about 4-5 weeks by now so you’re unlikely to get it before Xmas. That being said, the early bird gets the worm so get ’em while supply lasts 🙂

Rhea on the other hand is running a bit late, the MCU change means I need to rewrite some code and do a lot of testing. Still not sure if v2 will be good enough for sale but keep your fingers crossed. Oh, and I recently purchased a VCD/MPEG addon card to test compatibility – I know it’s not exactly frequently used and I don’t expect problems, but I’d like to be sure.

PCE is also deep in the woods, I had to restart proto PCB design on this project as well due to lessons learned from Saturn. In fact I’m going to do a simplified version first that will plug into a dev board (which in turn is getting upgraded from ARM7TDMI to CortexM4 next week) – it’ll be easier to work with, I don’t need it to be very portable yet.

Lastly I’m also getting a Mega Drive / Genesis + CD addon to look at the internals. This is completly on-the-side project with next to zero time assigned to it so please don’t expect any results soon. I won’t lie though, I like playing with new toys more than soldering all those GDEMUs 😛 This is something to keep me busy during December holidays, assuming I won’t be swamped with other work.

To sum up, you better hope I can keep my resolve not to play Civ:BE 🙂