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Why does nestest cycle count reset to 0?
http://forums.nesdev.com/viewtopic.php?f=3&t=15855
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Author:  nuker [ Tue Apr 25, 2017 1:16 pm ]
Post subject:  Why does nestest cycle count reset to 0?

I am just wondering why the cycle count for the nestest rom golden log goes from:

line 46: CYC: 333
line 47: CYC: 1

Is this something my emulator should be doing?

Author:  lidnariq [ Tue Apr 25, 2017 1:18 pm ]
Post subject:  Re: Why does nestest cycle count reset to 0?

CYC is measuring PPU X coordinate. It should range from 0 through 340.

Author:  nuker [ Tue Apr 25, 2017 1:20 pm ]
Post subject:  Re: Why does nestest cycle count reset to 0?

lidnariq wrote:
CYC is measuring PPU X coordinate. It should range from 0 through 340.


thanks for the response :). I am just trying to test my CPU at this moment and haven't started the PPU yet. Should I just print cycleCount % 341?

Author:  lidnariq [ Tue Apr 25, 2017 1:29 pm ]
Post subject:  Re: Why does nestest cycle count reset to 0?

PPU cycles are three times as fast as CPU cycles, e.g. "LDA #0" will cause the CYC count to increase by 6. But otherwise that's ... probably safe?

Author:  thefox [ Wed Apr 26, 2017 8:43 am ]
Post subject:  Re: Why does nestest cycle count reset to 0?

Just ignore the CYC value when you compare the logs.

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