5 ms·
257 would be impossible regardless 1,2,3,...,254,255,0,1,2,3... 1 byte. Although it is mentioned in the comments to the linked article that it is probably an
by camiller 10y ago
257 would be impossible regardless
1,2,3,...,254,255,0,1,2,3...
1 byte.
Although it is mentioned in the comments to the linked article that it is probably an electro-mechanical counter, so I am imagining a four wheel encoder with each wheel having 4 positions (although could be 8 wheels with 2 positions per wheel), electrically readable, and reset-able.
- jacquesm 10y agoTrains can be composed of all kinds of cars.
- camiller 10y agoyeah, but my point was that a mechanical counter of this nature would overflow counting 0-255 then wrapping around. So it would never get to 257. And the wheels I was referring would be in the counting mechanisim, I didn't say anything to suggest type of cars / axles etc.
- jacquesm 10y agoNo, that it won't get to 257 is the whole point here. So 257 axles with a single axle missed would end up as 256, resetting the counter -> no train present. Ditto for 255 with a single 'bounce'.
- camiller 10y agoI don't think that the article was about miscounts, otherwise it would equally be a problem for a 258 axle train that missed 2 axles. Since the article is describing a problem that occurs for multiples of 256 it is almost certainly a counter overflow issue, so a 256 axle train resets to zero and a 257 axle train would appear to the counter as 1, which is still sufficient to mark the block of track as occupied.