Re: [cc65] Char set questions

Date view Thread view Subject view

From: Jason Robertson (jkr_at_westol.com)
Date: 2002-05-23 16:27:21


On Wed, 22 May 2002 19:44:49 +0200, groepaz <groepaz_at_gmx.net> wrote:

>Hello Jason,

Hello Groepaz,

>JR> 1. Where in the C64 can I stick a char set that won't be touched by
>JR> the compiler/object code? Ie function code won't overwrite it etc.
>
>with cc65, i'd suggest putting it to either $0800 or (better but a bit
>harder to handle) to $e000 (you need to move videoram to sth like
>$e800 then aswell). the first solution is relativly easy to achive,
>just edit the ld65 script so it uses memory from $1000... not
>$0800..., but it will steal 2kb from your executeable.... the $e000
>solution would steal nothing from cc65's useable memory, but some
>screen-orientated functions might no more work (those who expect
>videoram at $0400)

Heh, a size vs. functionality issue. For game testing purposes right
now I'd probably use the first method.

>JR> 2. With a custom set in place and being used how will the conio
>JR> functions cprintf(), cputc(), and cputs() etc. be effected? I assume
>JR> that they'd be useable with the new set?
>
>uhmz, depends on their implementation :=) conio is usally done using
>direct-screen access, so i'd expect those to work on videoram at $0400
>only..... (they could be implemented differently though, but i dont
>think so). "normal" screen i/o (using the 3v1l kernal routs ;=)) can
>be done just like before, since the kernal routines support a moveable
>videoram. (i forgot how to tell them the new adress though, some
>zeropage adresses you can find in some book ;=))

Ah! or I can create some small inline asm code do handle as well ;-).
I'll have to see if I can find the zero page address for the kernal
routines, it'd be interesting to use those.

Thanks!

Jason
----------------------------------------------------------------------
To unsubscribe from the list send mail to majordomo_at_musoftware.de with
the string "unsubscribe cc65" in the body(!) of the mail.


Date view Thread view Subject view

This archive was generated by hypermail 2.1.3 : 2002-05-23 19:59:19 CEST