Re: Patching in a CBM disk drive connection in a C64 case.

On 3/28/22 16:34, tokafondo wrote:
> 
>  > Claudio Sánchez - Tokafondo wrote on 28.03.2022 14:39:
>  >
>  >> As part of some case mods I'm doing for fun, I've found that the CBM 
> disk drives designed to be used in a standard C64 are all external.
>  >> But both the SX64 and the C128D have internal drives.
>  >> What would be the least engineered way to have a CBM disk drive 
> connected to a C64 case?
>  >> I'm talking about something that would keep the ability to use 
> external drives or printers or whatever.
>  >> Maybe a sort of middle PCB that would sit on the CIA 2 socket, and 
> below the 6526 chip itself?
>  >
>  > Do you need to connect an existing drive (like 1541)? Or do you want 
> to create a completely new drive, perhaps in the style of C65's internal 
> dumb drive or CBM-II's planned low cost disk drive?
> 
> It's still a sort of "remix" of existing technologies. Taking internals 
> out of drives and putting them in a modded case with the C64.
> 
>  >
>  > For connecting a 1541, yes you can create a PCB to piggyback on the 
> CIA socket but not all C64's have socketed CIAs.
> 
> I was wondering if is there anyway to take the serial protocol out of 
> the communication between a C64 and a "not dumb" CBM drive and make both 
> talk about DMA.
> 
> There is a CBM drive already doing that, isn't it? One for the PLUS4 
> series, I think...

No, not using DMA, just a different I/O-port. That adapter you plug into 
the plus/4 contains a PLA (251641-03) and a 6523T (6525 in 28pin). There 
is no DMA involved.

  Gerrit