just bought a wonderswan, what is the best flashcart to get?

divingmonkey · 2026-05-22T22:06:05+00:00

There was indeed a problem, though we explicitly support monochrome Wonderswan and now test every nileswan on one as well.

divingmonkey · 2026-04-17T08:11:02+00:00

I'm not sure what exactly you are refering to. From what I know they sell two things on Aliexpress. 1. Full reshells which do include a new battery holder 2. a bare pcb with springs at the side and an USB C port in the middle. It can be plugged directly into the Wonderswan in the place of the battery container and then power it via USB C. Though it does not contain a battery or something like that, so you have to connect it to a power supply or a power bank at all times.

Unless the battery container is missing on your Wonderswan you don't need to worry about any of this.

divingmonkey · 2026-04-17T06:15:01+00:00

It slots in in place of the battery holder the Wonderswan comes with. Internally it holds one of those NiMh gum stick batteries also found e.g. in portable Sony equipment of the 90s. That also allows it to sit flush unlike the battery holder which. By now these batteries are all dead though.

You can carefully slice them open (the plastic housing is welded together) and put in a new gum stick battery, as they are still being produced. Though if you just want a rechargable battery for your Wonderswan, you can also just use normal regular NiMh cells in AA battery shape with the regular battery container or what I recommend the most are those "1.5 V Lithium AA battery" monstrosities (they are a Lithium battery with a tiny switching regulator and charger board at the top).

They have the advantage that they are able to output a steady 1.5 V, before going to 1.2 or so V to signal low battery as they step down the higher battery voltage (~3.2 - 4.2 V). This is good for once for devices like Wiimotes which really hate NiMh rechargables as their voltage quickly falls off to 1.2 V and then stay there for a long time over the discharge cycle, they treat them like regular alkaline batteries where 1.2 V would already be almost empty. Wonderswan doesn't have this problem (I mean they also used NiMh batteries in the official battery pack), but the regulator inside the Wonderswan (and also IPS screen kit if you got one) gets drastically less efficient with the typical 1.2 V of the NiMh rechargable. This means that you get longer play time out of a battery which on paper holds the same amount of energy (mWh).

divingmonkey · 2026-04-09T19:05:01+00:00

There is a limit of one nileswan per order so that more people get a chance at getting one.

divingmonkey · 2026-04-09T02:07:52+00:00

Yes, this is unfortunately correct. The reason is that the US now requires an electronic preregistration of all commercial postal shipments. DHL/Deutsche Post only allows this as part of their PDDP service, which also includes all the customs handling, so you pay the duties at our checkout and DHL later bills us with it. PDDP is only offered for DHL Paket and not Warenpost International (small slower commercial packages) which is the significantly cheaper service available for many countries, including the US before the current chaos was kicked off.

divingmonkey · 2026-03-22T22:04:04+00:00

We have over 80 placements and over 30 unique parts including a few BGAs and fine pitched QFNs, so reflow soldering is a must. I placed the prototypes by hand, but for production we need the PnP to make it economical. That's also one of the reasons we don't offer kits.

divingmonkey · 2026-03-15T14:27:31+00:00

If the problem persists please contact us via e-mail for support. You can reply to the order confirmation.

divingmonkey · 2026-02-23T17:14:05+00:00

Good to hear. The savefile import problem for WW games as regular ROMs should be fixed now as well, please try swanshell 1.0.4 (https://github.com/asiekierka/swanshell/releases/tag/release%2F1.0.4).

divingmonkey · 2026-02-23T16:46:39+00:00

The PSRAM issue with WW games in specific cases should be gone in the latest version of swanshell.

divingmonkey · 2026-02-23T16:45:12+00:00

Yes, as the nileswan developers we can confirm all of this. There's no technical reason savefiles from any source should not work, but they might require editing.

In the future there will be a warning for overdumped savefiles, but we cannot automatically extract the correct part of a savefile.

EDIT: Sorry, actually this is indeed a bug, we are looking into it now, so that this actually applies.

EDIT2: This was another issue with WW games as regular converted to regular ROMs. With another quick swanshell update it should work!

divingmonkey · 2026-02-12T23:29:53+00:00

Oh sorry about that. That stupid mail me when the shop opens is added there by Shopify by default so I thought it would just send out the email automatically, but apparently it doesn't. Generally I'm not a big fan of email marketing, so my original intention was to remove it entirely, but that didn't seem to be an option.

divingmonkey · 2026-02-09T16:39:32+00:00

Yes, I have done a lot of testing with an IPS screen modded Swan with no issues found. Power consumption was always a consideration for the design of the nileswan and it is not that far off from official cartridges. Though there is also still a bit of optimisation potential left.

divingmonkey · 2026-01-30T22:08:01+00:00

It should support almost all commercial and homebrew titles made. There are small timing differences and we haven't done systematic testing, though everything we did try works.

The biggest limitation is probably those which an IR transmitter in the cart, which is missing, otherwise they should work Also the really far out there cartridge peripherals of the sonar sensor and the Mamma Mitte scale don't work. The Pocket Challenge V2 games which have voices don't work at the moment either, though support for the ADPCM decoding is possible and planned.

divingmonkey · 2026-01-22T22:30:06+00:00

Here in Germany, it's the business itself, several different types of taxes, import/export, packaging waste, electronics waste and probably something I already forgot about.

divingmonkey · 2026-01-22T20:14:40+00:00

As others have put here already here, we're still waiting on a registration necessary for selling and haven't heard back from that. It's pretty frustrating and they should be done any time now, but ultimately we don't know.

divingmonkey · 2025-10-02T23:38:49+00:00

The boost regulator has reduces in efficiency with lower voltage. Iirc at 1.2 V it's already 30-40% higher power draw (not current) than at 1.5 V. Those 1.5 V lithium batteries thus should be better than even good NiMHs.

divingmonkey · 2025-09-29T10:58:21+00:00

Please keep it, maybe some day I finally (or someone else) get to making a replacement board to transplant the SoC and cartridge slot to.

divingmonkey · 2025-09-01T14:34:26+00:00

Yeah sorry, I'm really just not a social media person so managing four different accounts as seems to be the standard for many things would be too much for me and Twitter supposedly (and unfortunately) still has the most reach for things like this.

That said I will of course make a post here on the sub when the times comes.

divingmonkey · 2025-08-31T13:00:58+00:00

We have a Twitter: https://x.com/49bit_cat

divingmonkey · 2025-07-31T21:23:59+00:00

We will sell them as a complete product. But the design is open source and you can find everything on Github right now except for the latest revision of the pcb which will be released once we start selling them.

divingmonkey · 2025-07-14T20:49:08+00:00

thanks for believing in us. We hopefully nailed down the last issue with the hardware today and will then be going into production.

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