Path: utzoo!attcan!uunet!ncrlnk!ncr-sd!hp-sdd!hplabs!ucbvax!pasteur!buddy.Berkeley.EDU!c60b-rk
From: c60b-rk@buddy.Berkeley.EDU (Greg Burrell)
Newsgroups: comp.sys.cbm
Subject: Re: C64 LOAD Question
Keywords: help
Message-ID: <7217@pasteur.Berkeley.EDU>
Date: 8 Nov 88 22:15:52 GMT
References: <4984@whuts.UUCP>
Sender: news@pasteur.Berkeley.EDU
Reply-To: c60b-rk@buddy.Berkeley.EDU.UUCP (Greg Burrell)
Organization: University of California, Berkeley
Lines: 39

In article <4984@whuts.UUCP> rsw@whuts.UUCP (WITEL) writes:
>Hi, I'm having a problem with my C64.  I'm using the Kernal routine LOAD
>to dump approx 8k worth data from from my disk drive to RAM starting location
>#$4000. Three things are happening, either:
>		1.  Everyworks fine or
>		2.  Garbage is loaded into RAM or
>		3.  After 10-20 seconds of disk access the disk LED
>                    goes out and the progam gets hung up and only repowering
>                    the C64 will get me out of it.
>Does anyone have any insight on why #2 and #3 are happening
>Thanks in advance
>
>				Rod Witel
>				whuts!rsw
>				201 386-6447

It sounds to me like the load address is incorrect because
	1) It loads garbage - this could be becuase the load performed
	   correctly, but loaded into the wrong starting address.
	2) The program hangs up and the computer has to be reset -
	   you could have accidentally loaded over some important
	   memory locations used by the O.S.

	If you are trying to load FROM a machine language program 
(i.e jsr to kernel load vector), then have you set the correct load address
in the .X and .Y registers?

	However, if you are trying this from a BASIC program (i.e. SYS to
the load vector), then the BASIC SYS call will load the .A, .X, and .Y
registers from $030C, $030D, and $030E respectively BEFORE making the 
call to the load routine. Likewise, it will store the registers in these
locations after is returns from the SYS call. This could be a problem
if there are garbage values in these locations.


Hope this is of some help.


				-Greg