visual6502 bug report (irline3)

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cerebrum
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Joined: 28 Jan 2013

visual6502 bug report (irline3)

Post by cerebrum »

From:
https://github.com/trebonian/visual6502 ... denames.js
Quote:
irline3: 996, // internal signal: PLA input - ir0 AND ir1
But analysing the circuit I see that irline3 is actually ir0 OR ir1:

http://www.visual6502.org/JSSim/expert. ... &zoom=12.4

Edit: to clarify, the bug is just in the comment not in the code.
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BigEd
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Re: visual6502 bug report (irline3)

Post by BigEd »

Quite so: 1133 is the output of a NOR and it's followed by an inverter.

You can watch the signals like this:
http://www.visual6502.org/JSSim/expert. ... 3&steps=40

I've sent a pull request to Barry: anyone could do the same, by using the 'Edit' button on github - you need to be logged in, but accounts are free.

Cheers
Ed
cerebrum
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Re: visual6502 bug report (irline3)

Post by cerebrum »

Good, didn't know that I could edit the source.
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BigEd
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Re: visual6502 bug report (irline3)

Post by BigEd »

Note that Barry won't necessarily act immediately to pull requests! And it's another step to publish. So please bear in mind this is a volunteer website. For many experimental purposes, running your own fork in a 'gh-pages' branch is a good way to proceed.

Cheers
Ed
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BigEd
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Re: visual6502 bug report (irline3)

Post by BigEd »

OK, that fix is deployed now. You may need to force a refresh.
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