Re: [cc65] c64 kernal 02 vs. 03

From: Ullrich von Bassewitz <>
Date: 2009-09-26 17:34:25
On Sat, Sep 26, 2009 at 02:46:14PM +0200, Thomas Giesel wrote:
> 1) Call $ea24 from "plot" to make sure the color RAM pointer gets
>    synchronized
>    - That's not an official kernal entry, does it work on other kernals
>      (e.g. Jiffy and many other modified kernels)?
> 2) Check all of the callers which call $ea24
>    (
>    Maybe there's one we can use from an official kernal entry point?
> 3) Put the code from $ea24 into libsrc directly
>    - Only a few bytes, should be okay to add it to "plot" at
>      libsrc/c64/putc.s

You forgot 

  4) Do nothing and use a -03 kernal :-)

The question is: to which extent do we want to support different or especially
broken firmware ROMs? If it's the main firmware that is broken, we must
support it, if possible. But what's with much less popular broken firmware? A
few lines of additional code is not much, but a few bytes here and another few
bytes there are more than a few bytes in total. From my own ~10 C64 machines
and/or boards, none has a -02 kernal. Is it really so popular?



Ullrich von Bassewitz                        
To unsubscribe from the list send mail to with
the string "unsubscribe cc65" in the body(!) of the mail.
Received on Sat Sep 26 17:36:40 2009

This archive was generated by hypermail 2.1.8 : 2009-09-26 17:36:42 CEST