How the Commodore REU Works

I feel like it might be time to merge the channels together. Just saying

Rick Green

So I did see many posting the REU prices in YT comments, but I found an actual “Lycos Computer” ad from Apr ‘88 Compute’s Gazette listing the 1764 at $117 (!) and the 1750 as “call” , lol…

Talking about ram interfaces, been playing with this recently. https://github.com/cknave/c64-pico-ram-interface I had the pcb printed and it works fine and there are plenty of pico's around. It is a bit flaky as it uses DMA to move data between the C64 and the chip but still works well enough

Paul Bruner

Well, I had about 5 more episodes planned out. I just don't know when I'll ever have the time to make them.

The 8-Bit Guy

Anything 8 bit keys planned?

Mels Van Wees

It was a nice video and for me very informal. I never knew about this memory device, and about Sonic ;) as I'm not a commodore Guy , but a MSX one ;) Thank you for some nice vid again!

Edo van Zanten

I especially liked the technical coverage of the clock cycles. You mentioned blitters; I'd enjoy learning more about them in a future video.

I wish it was that simple with the Atari back then. Back in the 90s my brother bought a 256KB RAM kit for the Atari 800XL and I recall it involved him replacing several chips and soldering jumper wires. It failed to power up, so he had to send it somewhere (can't remember the place) where the fault was due to having a buggy 'B' revision of BASIC. They replaced BASIC chip with a revision 'C' and sent it back to us. With this RAM upgrade and also the Atari 130XE (with 128KB) it was possible to access the expanded RAM in 16KB bank blocks (32KB-48KB address range if I recall right) with a poke command. The only software I can recall utilising the extra RAM was some digital audio sound player and a RAM disk, but can't remember any software title.

Seán Byrne

So kind of like a modern day SSD?

On your main page click the "..." button on the right hand side and select "Manage Posts". Select the post you want and hit the "Edit" button. You'll see the video at the top of the screen. There's a hidden trash icon top right on the video (very hard to see). Click that and you can add the new video. I just had to do this and discovered it by accident!

Big Car

Thank you David for another great video!!! I had no idea the REU existed.

Robert Bontrager

It's impressive how the C64 version of Sonic actually runs better than the original Master System/ Game Gear version. It's easily possible for Sonic to outrun the screen on the Master System, but the Commodores can keep up with the Hedgehog.

Rick Green