Any plans for dual VIC-II support? (PAL / NTSC switchable)

Caution: Non registered users only see threads and messages in the currently selected language, which is determined by their browser. Please create an account and log in to see all content by default. This is a limitation of the forum software.


Also users that are not logged in can not create new threads. This is a, unfortunately needed, counter measure against spam. Please create an account and log in to start new threads.

Don't Panic. Please wash hands.
  • I'm curious if there are plans to offer support for dual VIC-II chips to make it possible to fit both NTSC and PAL versions, allowing them to be switchable (after a reset or power cycle)? Maybe an add-on adapter board to hold and switch between the two chips, maybe an MK3 release with 2 VIC-II sockets?


    There's an existing product to do this which is compatible with 3 original C64 motherboard assemblies called VIC-II², which I'm sure most here know about. Can this product work with C64 Reloaded MK2?

  • I've checked the schematics of that thing and I must say I'm shocked that someone would rely on a chip to go completely tri-state when it's not getting any power. The proper way of switching between the two chips is to keep them powered and do multiplexing on the digital side. That involves LOTS of chips and is certainly not possible for a low price.


    Further, chip recognition should also continue to work on the C64RMK2, and for best convenience, you should be able to mix and match 65xx and 85xx chips - the latter obvioulsy behave differently when not powered, otherwise the kit wouldn't be advertised as "works in old boards only" (haven't read the full forum thread on Amibay).


    I strongly recommend to not use it. It is a typical "works by accident" and not "by design" thing. The behaviour of the chip's signal pins when not powered is not specified, hence the design relies on assumptions. You know what they say about "ASSUME" - it makes an "ASS of U and ME".

  • The last reply was more than 365 days ago, this thread is most likely obsolete. It is recommended to create a new thread instead.