The manuals ("Guide to the Macintosh Family Hardware", second and
third editions, and "Designing Cards and Drivers for the Macintosh
Family", second edition) are in error. The signals and signal
descriptions are correct, but the key for the slot is off by 180
degrees (that is, columns A and C should be swapped, as should be
rows 1 and 32).
The manual "Designing Cards and Drivers for the Macintosh Family",
third edition, has been updated and the Macintosh Portable PDS diagram
has been corrected.