Subject: Re: [stella] Re: Help with efficient code From: Eckhard_Stolberg@xxxxxxxxxxxxxxxxxxxxx (Eckhard Stolberg) Date: Tue, 30 Sep 1997 16:52:07 +0200 |
>Whoops! Forgot about jmp (abs,x) which I remembered as a 65816 opcode. >Sorry... and thanks to Amos Bannister for the reminder (btw, the >instruction works differently than his example.) I couldn't find this addressing mode in any illegal instuction reference. Are you sure it exists on the 6507? By calculating the opcode with one of my references I got $40 for 'jmp (abs,x)', but this is the opcode for 'rti'. Since the 6507 doesn't have any interrupt support, does $40 work as 'jmp (abs,x)' on the 6507? Or has this something to do with the I-flag not being set? Thanks, Eckhard Stolberg -- Archives updated once/day at http://www.biglist.com/lists/stella/archives/ Unsubscribing and other info at http://www.biglist.com/lists/stella/stella.html
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