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Fix cpu6 detect #34
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Fix cpu6 detect #34
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Needs to set V flag depending on value for various cpu6 detection code to work
Now cpu6 detection works, code actually executes these
Sonic-Amiga
reviewed
Jul 20, 2022
| alu_out ^= ALU_V; | ||
| // Explicitly clears L and F flags | ||
| alu_out &= ~(ALU_L | ALU_F); | ||
| logic_flags(v); |
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Would be neat if you describe CPU detection logic somewhere.
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As a comment?
Code just executes a clr to a non-zero value and checks the v flag. As CPU5 doesn't implement "small immediates", it clears to zero and v flag is zero.
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Aha, got it. CPU5 ignored the remaining nibble of the operand, where the constant was pushed in in cpu6.
Still perhaps worth leaving somewhere. In code comments or maybe on wiki.
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Ah so we finally know wtf was going on. Cool
Sonic-Amiga
approved these changes
Jul 20, 2022
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CLR needs to set V flag depending on value for various cpu6 detection code to work.
Also stub parity enable/disable.
Allows
?DSKTto correctly detect and report that it's running on cpu6Before:
After