Thank you so much for making this video!

@RetroWK

2 жыл бұрын

Thanks for watching! My pleasure!

You soldered the surface mount pretty okay. Lots of flux and thin solder tin and you’re on your way. This was really nicely done.

@RetroWK

2 жыл бұрын

Thanks! I did a few and the last ones looked pretty decent ;-)

Awesome!! Great Video!!!! and another Commodore video so soon after the last one!!! Wish you had done this video 2 or 3 months ago before I paid $750 for the "Huge C128 lot and monitor" off of eBay!!! I bought that lot for the two Commodore 256K and 512K REU's and a working 1581 drive. Well, I probably would have still bought it just to get the 1581 drive! I have always wanted to have one of them and it look amazing sitting next to my C128D and 1902 monitor! I have a feeling that a lot of these will be made now with the release of Sonic the hedgehog for the C64 and it is needing at least a 256K REU to run. I love all of your work and you have a great voice for doing this! Thank you!!!

@RetroWK

2 жыл бұрын

Thanks! ... as always!!

YES! I was waiting for this, I can't wait to play sonic now with this and an sd2iec.

@RetroWK

2 жыл бұрын

Sonic is not yet ready for this ... and I am not sure if it will be. I don't know enough about the internals of Sonic to be 100% sure about if it is possible to port Sonic to use GeoRam/NeoRam. Other games like Eye of the Beholder or Neuromancer did it ...

@rxblackpill

2 жыл бұрын

@@RetroWK Ah yes, I caught you mentioning it at the end there. I always seem to get too excited when REUs are mentioned. It's a very fun concept, but there is very little software that takes advantage of things like the 1750 or 1764, not to mention the need of another PSU. NeoRam is definitely interesting and I think I might have to do some research to figure out more of the benefits it can provide. The differences of something like the 1764 compared to Geo/NeoRam is interesting as well. It's just a shame the architecture limits the usefulness of both. It's great that NeoRam is open source and easy to build however, I have read on forums that it might have a bit more potential to support all kinds of software (as demonstrated by you)!

@RetroWK

2 жыл бұрын

@@rxblackpill I will do a follow up to show what you can do with NeoRam.

The challenge to keeping the cost down is finding ram affordably. I tried two separate batches from aliexpress, both either fakes or rebadged. I wound up having to get them from a reputable source for about $5 US each plus shipping.

@RetroWK

2 жыл бұрын

I got mine from my local parts dealer Reichelt. 4 for € 15,65. That's almost fair :-)

@Charleshawn66

2 жыл бұрын

Hello Jason, could you share that reputable source so I don't have to go through what you did with aliexpress.? Thank you.

Nice job on those surface mount chips. :)

@RetroWK

2 жыл бұрын

Thanks!

I believe that Sonic uses the DMA capabilities of the REU to copy screen and sprite data into the VICII's memory bank. This is done without the CPU and is why it can scroll the screen and colour memory so fast.

@RetroWK

2 жыл бұрын

After all the debate I decided to get to the source. I will talk to Mr. Sid on Thursday and then we will know for sure.

@NickFellows

2 жыл бұрын

@@RetroWK Will be really interesting to find out , i thought the Sonic game used the Safe VSP trick. still be interesting to find out if the DMA feature could be added cheaply.

Looking forward to building a few of these. Maybe RAM chips should be soldered first then sockets and stuff?

@RetroWK

2 жыл бұрын

Yep. That is recommended. The other way around works fine too, but it is easier when the board is empty.

Excellent build! I am very interested to see if this emulates an REU enough to run Sonic. I've got a SideKick64 that can work as a GeoRAM module but Sonic isn't happy with this.

@RetroWK

2 жыл бұрын

Nope, not without Sonic actively supporting it. Sorry! I don't know enough about the internals of Sonic to be 100% sure about if it is possible to port Sonic to use GeoRam/NeoRam. Other games like Eye of the Beholder or Neuromancer did it ...

@Charleshawn66

2 жыл бұрын

@@RetroWK Well now I don't feel so bad about spending all that money to get that lot with the two Commodore REU's.

@Mr76Pontiac

2 жыл бұрын

@@Charleshawn66 Sonic comes with a note with recent versions that original REUs won't work at the 128s 2mhz speeds due to timing issues. I cannot test this as I don't have an original REU (I traded it for the 128 Programmers Reference manual) and I "only" have the U2+ to work with, which works superbly.

@tetsujin_144

2 жыл бұрын

The thing is, the original Commodore REUs weren't just RAM expansion, they also incorporated a memory controller that could bulk-DMA-copy data between the C64 RAM and the REU expansion RAM independently of the CPU. This is very useful for games because they can use it to update display RAM, for instance. geoRAM used a simpler scheme - instead of copying RAM back and forth between system RAM and the expansion, the expansion places a portion of the expansion RAM directly in the CPU's address space (shadowing some portion of system RAM) - and you can bank-switch to access different areas of the expansion. The benefit is you don't need to copy the data back and forth - you can directly access a little piece of it at a time - but you don't get the benefit of those DMA transfers.

@Charleshawn66

2 жыл бұрын

@@tetsujin_144 TY for teaching me something!! I'm 55 and still learning things about my C64 that I got for Xmas 1983.

I'd love for someone with way more skills than me to make a CMD SuperCPU-like accelerator for the C64 that plugs into the cartridge port just like the original did, but it could use an FPGA instead of a 65C816S which would allow it to do even more amazing things, like run at mind-blowing speeds probably well over 100mhz. Imagine what kinds of games you could create for the C64 even if the only difference was a processor running at, say, 300-500mhz....

@RetroWK

2 жыл бұрын

That would be very cool ... and would need someone with way way more skills than I have ;-)

@Promilus1984

2 жыл бұрын

Nah, it wouldn't make all that much difference when it comes to games. Remember that VIC accesses it's RAM block in the fixed time - it's video memory stays the same in terms of both speed and size. So at some point giving more powerful CPU looks like pairing up Riva TNT with 13th gen Core i9. While it still might be faster in some aspects most of the game will run basically the same as on e.g. Athlon 800MHz. Just because Riva will be a bottleneck. And in C64 with SuperCPU original hardware memory access is limiting factor. Having that said - sure there is some work to get W65C816S FPGA implementation but not exactly for C64 CMD SuperCPU compatible cartridge. Given shortages of FPGA and rapidly growing prices I'd say compact and relatively cheap FPGA from manufacturer outside of mainstream - like Lattice or GOWIN - might be a reasonable solution. And with GW1NR having embedded flash and/or ram I bet that one might be a neat and compact all-rounder.

Seems logical that one could add a flash rom containing something like the sonic port. It opens up the possibility for physical releases , new games that use the REU without people needing to already have one. I've paid £39 for a modern C64 cartridge game so clearly theres margin for profit there if they can be made this cheaply.

@RetroWK

2 жыл бұрын

The problem is, that the REU has custom hardware that is not present on the GEORAM / NEORAM. That's why Sonic doesn't work ...

@JustWasted3HoursHere

2 жыл бұрын

In fact there's a new advanced BASIC for the C64 called "Vision BASIC" that requires 256K but recommends 512K. This is required only during creation and compilation. After that the game itself can be made to run on a stock C64 or I believe it can take advantage of expanded RAM. kzread.info/dron/o0HyoOLjJlNvy2K-SDNP8A.html

Would like one myself,. full 2G and battery

@Charleshawn66

2 жыл бұрын

2G I wish!! its 2MB when maxed. That would be cool if that could happen!

@RetroWK

2 жыл бұрын

(in Emporer Palpatines voice): Do it!

now add an fpga and a stm32 wit esp32, now its a $70-100 upgrade, just need software support first...even 32k dual port sram is cheap

@Clancydaenlightened

Жыл бұрын

direct binary and rom flashing via wifi!

@Clancydaenlightened

Жыл бұрын

can just connect to a rom download unzip extract, and write contents to memory, wit dat fpga, stm32, and esp32 it'll be fast too! can even add a micro sd slot...and its own rom with its own custom os and routines better than stock shit

@Clancydaenlightened

Жыл бұрын

got enough co-processing and dsp power to actually run a usable gui os on an 8bit machine, could throw a pic32 chip in which has built logic for display and graphics processing

@Clancydaenlightened

Жыл бұрын

can throw an ay8910 or 8930 for sound expansion and dat 16bit gpio port, hook it up to a db-25 and connect anything you want, get a dac chip and boom digital audio too! well dat pic, stm or esp probably has some sort of dac capability somewhere, shit if dat fpga has some config blocks left over just throw it in dat, or maybe cram everthing even into a cpld instead

I guess it's not REU compatible?

@RetroWK

2 жыл бұрын

Nope, it is not.

REU alternative ?

@RetroWK

2 жыл бұрын

Depends on what you plan to do with it. The REU had some logic inside which this one does not. So it's not a plug&play replacement. There is software out there. Everything that runs with GeoRam or NeoRam runs with this. I hope they port Sonic to use GeoRam/NeoRam.

@Mr_Meowingtons

2 жыл бұрын

@@RetroWK You can't port Sonic to run with out the DMA controller. with it out the ram can not move faster enough.

@RetroWK

2 жыл бұрын

@@Mr_Meowingtons I don't know about the internals of Sonic. If they use the extended memory to store assets (graphics, music etc.) then it would work. If they use it as a screenbuffer or something, then it would be almost impossible.

the drawback of owning a 1541u2+ ,everything is there......i want to build but no need to use accessories..even though i want to build =)

@RetroWK

2 жыл бұрын

I know what you mean ;-) Often the fun is in building (and not using)!

Going to sell them ?

@RetroWK

2 жыл бұрын

I didn't plan, but since there is demand I will build a few. I just ordered parts. So if you want one, please send me an E-Mail wolfgang AT wolfgangkierdorf DOT de