playing with cross-assemblers

jokker · Post by **jokker** » Thu Nov 13, 2008 4:25 pm

Hi All,

So I'm new to VIC-20 asm stuff and I've been messing with CC65 and DASM trying to get this little interrupt handler going but I can't seem to load it properly in VICE

irq.asm
processor 6502
org $033c

sei
lda #$49
sta $314
lda #$03
sta $315
cli
rts
lda 203
sta $1e00
lda #0
sta $9600
jmp $eabf

So just this example I found on the net that I didn't think was too hard to play with
http://www.atarimagazines.com/compute/i ... errupt.php

I can get it to assemble into a proper block of code and even verify the first byte is the right load address, however I load it up with load"irq",8 and when I look at the contents of memory at $033c I don't see the instructions..

So I figure I missing something and heck maybe a few things that I'm sure all those more up to speed could point out to me!

Thanks in advance
_Troy

formater · Post by **formater** » Thu Nov 13, 2008 5:16 pm

To load non relocatable code, you must use load "name",8,1
Is use load "name",8 the system asume the start of basic as init of load

rhurst · Post by **rhurst** » Thu Nov 13, 2008 6:59 pm

LOAD "your.prg",8,1
SYS 828

All that interrupt-driver routine is going to do is keep a fixed character stored on the screen's home position... assuming it is an unexpanded VIC 20 (3583 bytes free). If running xvic emulator, pass it the "-memory none" parameter, too.

FYI, $033C is the start of the VIC's cassette buffer memory... so don't use tape! ;^)

jokker · Post by **jokker** » Thu Nov 13, 2008 9:05 pm

Thanks for the tip!

I got it backwards, I though without the ,1 was for loading non-relocatable code...

Yeah that's basically all I wanted as a starting point to learn from, expand upon and so forth. I done enough of the readying but now it's time put things into practice and starting writing some code!