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Update documentation.

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David Given
2019-07-03 01:00:05 +02:00
parent 54d0003368
commit 41b99b7f9d
16 changed files with 79 additions and 73 deletions
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doc/problems.md
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@@ -133,14 +133,14 @@ probably never need to touch them.
Clock detection
---------------
A very useful tool for examining problematic disks is `fe-inspect`. This will
let you examine the raw flux on a disk (or flux file). It'll also guess the
clock rate on the disk for you, using a simple statistical analysis of the
pulse intervals on the disk. (Note that the tool only works on one track at a
time.)
A very useful tool for examining problematic disks is `fluxengine inspect`.
This will let you examine the raw flux on a disk (or flux file). It'll also
guess the clock rate on the disk for you, using a simple statistical analysis
of the pulse intervals on the disk. (Note that the tool only works on one
track at a time.)
```
$ fe-inspect -s good.flux:t=0:s=0
$ fluxengine inspect -s good.flux:t=0:s=0
Clock detection histogram:
3.58 737 ▉
3.67 3838 ████▊
@@ -192,7 +192,7 @@ So, what does my Victor 9000 histogram look like? Let's look at the
histogram for a single track:
```
$ fe-inspect -s dubious.flux:t=0:s=0
$ fluxengine inspect -s dubious.flux:t=0:s=0
Clock detection histogram:
1.33 1904 █▉
1.42 21669 ██████████████████████▌
@@ -241,15 +241,15 @@ That's... not good. The disk is very noisy, and the intervals between pulses
are horribly distributed. The detected clock from the decode is 1.45us, which
does correspond more-or-less to a peak. You'll also notice that the
double-clock interval is at 3.00us, which is _not_ twice 1.45us. The guessed
clock by `fe-inspect` is 1.67us, which is clearly wrong.
clock by `fluxengine inspect` is 1.67us, which is clearly wrong.
This demonstrates that the statistical clock guessing isn't brilliant, which
is why I've just rewritten the decoder not to use it; nevertheless, it's a
useful tool for examining disks.
`fe-inspect` will also dump the raw flux data in various formats, but that's
mostly only useful to me. Try `--dump-bits` to see the raw bit pattern on the
disk (using the guessed clock, or `--manual-clock-rate-us` to set it
`fluxengine inspect` will also dump the raw flux data in various formats, but
that's mostly only useful to me. Try `--dump-bits` to see the raw bit pattern
on the disk (using the guessed clock, or `--manual-clock-rate-us` to set it
yourself); `--dump-flux` will show you discrete pulses and the intervals
between them.