Re: Multi-ROM built, what now?

From: Mike Naberezny <>
Date: Wed, 05 Jun 2013 12:23:51 -0700
Message-ID: <>
Hi Ruud,

On 6/2/13 11:20 PM, Baltissen, GJPAA (Ruud) wrote:
> I finished building the hardware enabling me to choose a ROM combination.
> This can be done using an extra 6522. This also means I can implement a ROM
> that needs more than the standard 16 KB using the paging method. But now
> the question: where can I use it for?

A bank-switched ROM could be used to enhance JiffyDOS 64:

  - Eliminate the switch.  Most JiffyDOS users have a mechanical switch to 
select between JiffyDOS and the stock KERNAL.  Instead of the switch, have the 
machine always start up with JiffyDOS and add a new command to bank in the 
stock KERNAL.  It would be used like "GO 64" on the C128.

  - Restore tape support.  JiffyDOS does not have tape support because the 
routines were replaced with other features.  It would be nice to have tape 
support without having to switch back to the stock KERNAL.

  - Add JiffyMON.  This is a nice machine language monitor for use with 
JiffyDOS that is loaded from disk.  According to the manual, it loads into the 
RAM underneath the KERNAL ROM.  Put it in the banked ROM instead so that it is 
always available.


Mike Naberezny (

       Message was sent through the cbm-hackers mailing list
Received on 2013-06-05 20:00:12

Archive generated by hypermail 2.2.0.