rsw@whuts.UUCP (WITEL) (11/04/88)
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
201 386-6447c60b-rk@buddy.Berkeley.EDU (Greg Burrell) (11/09/88)
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