Switchless JiffyDOS kernal switcher?

[8bitDenial]

My C64 was bought from the same seller as my recent Vic-20 purchase.

However, the 64 came fitted with a switch-less kernal switcher which starts the C64 in JiffyDOS, but changes to the standard kernal if powered on with the Restore key held down.

I purchased the Vic-20 JiffyDOS kernal overlay images and would like to add JiffyDOS, making it behave in the same way as the C64 (i.e. JiffyDOS kernal by default, hold down the Restore key on power-on to get the standard Vic-20 kernal).

Would the same switcher as fitted into my C64 work in the Vic (assuming I burn the correct ROM) and if so, where could I buy a switch-less kit to place an EPROM into?

[srowe]

The RESTORE key handling in the C64 is quite different to the VIC, it goes through a 7474 flip-flop if I recall. Do you have a photo of how this is wired up in the C64?

[8bitDenial]

Thank you.

I'll check and upload a photo.

[srowe]

If it's this device

https://github.com/bwack/C64-Switchless ... 56-adapter

Then it uses the EXROM signal from the PLA. There's no equivalent of that on the VIC-20.

[MCes]

Have a look here:
http://sleepingelephant.com/ipw-web/bul ... php?t=9482