|My Panasonic KX-P1524 has a label above the interface connectors (in back) which describes what each of the switches is for. They control such things as character set, interface details, etc.|
The switches are in three groups (DIP SW 1 through DIP SW 3), and each group has eight switches (designated 1-1 through 1-8, 2-1 through 2-8, and 3-1 through 3-8).
The descriptions of the switch settings are cryptic, but someone experienced in the technology of that period should be able to decipher most or all of them. If you need help on that, IBM used to sell these printers, apparently, and they published an instruction sheet mentioned in the previous reply. It has less cryptic descriptions of the DIP switch functions.
Note: The front panel switches can be used for some of the same functions as the DIP switches. See the IBM sheet for more details.