Hi Jan,
The ANDA instruction will perform a logical and of the contents of register A with the immediate value argument. Register A being the eight most significant bits of register D. In your example, it's performing a logical and on the most significant bit of register A.
Cheers,
Chris
I'm not really that far into the disassembly yet, but what I find at that point of the code is this:
The ANDA instruction will perform a logical and of the contents of register A with the immediate value argument. Register A being the eight most significant bits of register D. In your example, it's performing a logical and on the most significant bit of register A.
Cheers,
Chris
From: oberheim@yahoogroups.com [oberheim@yahoogroups.com]
Sent: 10 September 2014 20:52
To: oberheim@yahoogroups.com
Subject: [oberheim] Re: Faster CPU & firmware mod for the Oberheim Matrix 1000
Sent: 10 September 2014 20:52
To: oberheim@yahoogroups.com
Subject: [oberheim] Re: Faster CPU & firmware mod for the Oberheim Matrix 1000
I'm not really that far into the disassembly yet, but what I find at that point of the code is this:
ANDA #$80 *C693: 84 80 '..'
So, no adding, rather an AND, so the patch value would rather have to be 0x7F - or am I wrong there?