Correction: "text strings", not "test strings" (see below)


This is a big document, so here is where to find the highlights:
* The message descriptions start in section 7.6.8
* There is an ascii-to-6bit mapping, shown in table 23, that is used to
encode test strings. This is not the same thing as the 6bit-to-ASCII
mapping, so don't get confused (as I did at the start of this string)
* The 6bit-to-ASCII is described starting at section G.3.6
* Examples of AIS NMEA sentences are shown in section G.3.2

-Paul