Update AES Lanier documentation.

doc/aeslanier.md

@@ -1,4 +1,39 @@
+AES Lanier word processor disks
+===============================
+
+Back in 1980 Lanier released a series of very early integrated word processor
+appliances, the No Problem. These were actually [rebranded AES Data Superplus
+machines](http://vintagecomputers.site90.net/aes/). They wrer gigantic,
+weighed 40kg, and one example I've found cost £13,000 in 1981 (the equivalent
+of nearly £50,000 in 2018!).
+
+8080 machines with 32kB of RAM, they ran their own proprietary word
+processing software off twin 5.25" drive units, but apparently other software
+was available.
+
+The disk format is exceptionally weird. They used hard sectored disks, where
+there were multiple index holes, one for each sector. The encoding scheme
+itself is [MMFM (aka
+M2FM)](http://www.retrotechnology.com/herbs_stuff/m2fm.html), an early
+attempt at double-density disk encoding which rapidly got obsoleted by the
+simpler MFM. Even aside from the encoding, the format on disk was strange;
+unified sector header/data records, and 253 (or maybe 252) byte sectors.
+
+FluxEngine can read these, but I only have a single, fairly poor example of a
+disk image, and I've had to make a lot of guesses as to the sector format
+based on what looks right. If anyone knows _anything_ about these disks,
+[please get in touch](https://github.com/davidgiven/fluxengine/issues/new).
+
+Reading discs
+-------------
+
+Just do:
+
+```
+.obj/fe-readaeslanier
+```
+
 Useful references
 -----------------
 
-  * [SA800 Diskette Storage Drive - Theory Of Operations](http://www.hartetechnologies.com/manuals/Shugart/50664-1_SA800_TheorOp_May78.pdf)
+  * [SA800 Diskette Storage Drive - Theory Of Operations](http://www.hartetechnologies.com/manuals/Shugart/50664-1_SA800_TheorOp_May78.pdf): talks about MMFM a lot, but the Lanier machines didn't use this disk format.

doc/index.md

@@ -84,6 +84,7 @@ Here's the table.
 | IBM PC compatible                 |  🦄   |        | and compatibles (like the Atari ST) |
 | [Acorn ADFS](acornadfs.html)      |  🦖   |        | single- and double- sided           |
 | [Acorn DFS](acorndfs.html)        |  🦄   |        |                                     |
+| [AES Superplus / No Problem](aeslanier.html) |  🦖   | | hard sectors! and _very_ experimental |
 | [Ampro Little Board](ampro.html)  |  🦖   |        |                                     |
 | [Apple II DOS 3.3](apple2.html)   |  🦖   |        | doesn't do logical sector remapping |
 | [Amiga](amiga.html)               |  🦄   |        |                                     |