Thanks for the feedback.
The readreg has changed slightly. The rightmost "description" field is nothing more than a hint.
The "operational" registers tend to be the same for the "8-bit parameter" style of controllers.
But the "configuration" registers vary greatly for different models and manufacturers.
e.g. the controller ID register and format varies.
e.g. the "Manufacturer ID" is not always filled in.
David.