MiSTer FPGA Forum

I was wondering if there’s a list for Cores that don’t require SDRAM addon and which require 32MB, 64MB, 128MB, etc?

I remember watching a YouTube video mentioning it but maybe there’s a running list or chart?

This is changing all the time, but it would be a nice idea to list on the README for each core.
For example, about 1-2 months ago, we removed the requirement of SDRAM from the TRS-80 core.

Oh, and you should consider that 64MB is not really a supported configuration - only 32MB and 128MB. And very few need 128MB (I understand that this is only a small number of Neo Geo games).

Anyone know of MB chart for the mister compatibility?

edit: some neo geo info on 32/64/128. https://github.com/MiSTer-devel/NeoGeo_ ... omsets.xml

dshadoff wrote: ↑Sun Jun 14, 2020 7:52 pmAnd very few need 128MB (I understand that this is only a small number of Neo Geo games).

My understanding is that GBA games 32 MB and larger also potentially benefit from 128 MB SDRAM because:

1) Stuff other than cartridge ROM is stored in the SDRAM, so you need SDRAM larger than the cartridge size to store it in SDRAM
2) While the GBA core is able to store cartridge ROM in DDR3, this involves some timing compromises that can have performance or compatibility implications. I don't think anyone has made a list, but I bet there would be a solid correlation between such a list and games that had problems on first-gen GBA flash carts (which IIRC weren't as fast as licensed cartridges and often required games to be patched to configure more wait states). I'm not sure where to find such a list today because that stuff hasn't been relevant for 15+ years, though.

As the GBA core uses a cache for Cartridge data, it doesn't really matter if SDRam or DDR3.
You may receive a little bit higher fastforward speed with SDRam and games that frequently fetch random data from Cart (e.g. Kirby Amazing Mirror for every new enemy or soundsample), might be influenced a tiny bit in steady audio/video output.
Having said that, i never noticed it myself and i developed most parts of the core using only DDR3.

However, this sentence in the wiki is wrong:
GBA: "will automatically use the onboard DDR3 RAM instead if SDRAM is not large enough"

if you have 32Mbyte SDRam and memorytype is set to SDRam or Auto and you start a 32Mbyte Rom (e.g. Fireemblem 2 or Kingdom Hearts), it will not work, until you select DDR3 memory type by hand.
There is no autodetection for this rare case currently.
A Github bug entry exists for that topic.