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Re:Clocking a 6502 simulator to 15GHz by paulmd on Monday April 13, 2020 @05:45PM (#22860457)
"until pins stop wiggling"?
Re:Clocking a 6502 simulator to 15GHz by variaga on Monday April 13, 2020 @06:06PM (#22860709)
The pins don't physically wiggle. "pins wiggling" is a common metaphor for "the voltage level on a pin is changing".

As a signal driver is toggled at increasing frequencies ('cranking up the clock'), the signal amplitude (voltage difference between the 'high' and 'low' period) starts to drop. At a high enough frequency, the signal will be indistinguishable from noise and 'stops wiggling'.

Re:Clocking a 6502 simulator to 15GHz by duskwuff on Monday April 13, 2020 @06:38PM (#22860960)
> At a high enough frequency, the signal will be indistinguishable from noise and 'stops wiggling'.

It's not that the signal will be indistinguishable from noise, but that the CPU will stop working correctly, so its outputs will stop toggling (or will toggle in unexpected ways).

Re:Clocking a 6502 simulator to 15GHz by numpad0 on Monday April 13, 2020 @11:47PM (#22862579)
I had an impression that they might be talking what a digital I/O pin looks on oscilloscope.

Scopes lock at first rising edge after last horizontal scan, so display starts at H, then drops to L after how long CPU held that pin high. That creates  ̄ ̄l_ lines on the screen superimposed to one another, X position “wiggling”  ̄lll_ depending on how many consecutive H bits just happened to be sent.

When the CPU halts, the pin would flatline at H or L and you’ll know.

Re:Clocking a 6502 simulator to 15GHz by kabdib on Monday April 13, 2020 @10:10PM (#22862128)
I was actually thinking about catastrophic failure, as in something on the chip burning out and making the clock stop.

My guess is that they were probably cooling it with beer (or at least cold beer bottle bottoms) to get that last critical Mhz, before drinking the beer.

Re:Clocking a 6502 simulator to 15GHz by mmastrac on Monday April 13, 2020 @06:04PM (#22860690)
Wiggling a pin - ie: toggling it. Basically means "activity on the pins"

https://www.cypress.com/blog/technical/more-pdl-examples-wig...

Re:Clocking a 6502 simulator to 15GHz by metaphor on Monday April 13, 2020 @06:08PM (#22860731)
Euphemism for when you don't see output pins transition state on a measuring instrument, e.g. oscope.
Re:Clocking a 6502 simulator to 15GHz by justwalt on Monday April 13, 2020 @06:03PM (#22860673)
I think it should be “start wiggling” as that makes more sense.
Re:Clocking a 6502 simulator to 15GHz by brokenmachine on Monday April 13, 2020 @08:24PM (#22861655)
Wiggling pins is what a computer does when it is working.
Re:Clocking a 6502 simulator to 15GHz by xentripetal on Monday April 13, 2020 @05:56PM (#22860600)
Maybe the pins got so hot they melted into the board?