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From: mock@iris.ucdavis.edu (Kenrick J. Mock)
Newsgroups: comp.sys.apple2
Subject: Re: Orca/C/M...Ack!
Message-ID: <8393@ucdavis.ucdavis.edu>
Date: 17 Feb 91 18:10:52 GMT
References: <28630.27bd478e@kuhub.cc.ukans.edu>
Sender: usenet@ucdavis.ucdavis.edu
Reply-To: mock@iris.ucdavis.edu (Kenrick J. Mock)
Organization: U.C. Davis - Dept of Electrical Engineering and Computer Science
Lines: 59

Here is an easy way to mix Orca C and Orca M together.  Here is the general
structure of your Orca/M file:

************************************************************************
         keep  myprog
MYPROG   start
* init stuff.  Set data/prog bank
         phk
         plb
* maybe save processor status as well and disable interrupts if necessary
         php
         sei
* Your program goes here
         lda somevar
         ...
         WDM        ; Your code goes here, do something with somevar
         ...
* Quit code.  Load a #0 as the returning value
         plp
         lda   #0
         rtl
SOMEVAR  entry      ; Declare SOMEVAR as external entry point
         dc H'00 00'
         end
************************************************************************

From the shell, ASML MYPROG.

Here is what the C program can look like:

/********************************************************************/
#pragma keep "CPROG"
extern void MYPROG(void);       /* Declare external parameters */
extern void SOMEVAR(void);
main()
 {
  word *asmparm;

  asmparm=(word *) SOMEVAR;
  *asmparm=0x0101;              /* your parameter */
  MYPROG();                     /* Call the assembly procedure */
 }
/********************************************************************/
Compile CPROG.CC.  Then do a "link cprog myprog keep=cprog" and the 
resulting EXE file will execute your Orca/M code.  This method is a little
simpler than passing in parameters through the stack, although it is not
as clean.  Opponents of global variables are certain not to like it...
In any case, I hope it helps.

Ken

P.S. Play Columns!  Oh, also, if all you want to do is load and
display a $C1 picture, you can load it directly to $E12000 and the
picture will load right to the SHR screen.

------------------------------------------------------------------------------
    "When you make your mark in the world, watch out for guys with erasers."
      - Wall Street Journal.
GEnie : K.MOCK        Net : mock@iris.ucdavis.edu, mock@alderon.lanl.gov