Hi Mosaic,
As one example, I use sixteen EEPROM frequency-to-band data "memories" in my PIC based Amateur radio Antenna Selector. The Antenna Selector monitors a 1-wire Icom CI-V serial buss looking for "frequency change" broadcasts from my Icom transceiver (which occur when you move the tuning dial or change bands, etc.).
The Antenna Selector compares the frequency in its frequency-to-band data "memories" to the frequency contained in the "frequency change" broadcasts and will energize the correct antenna change-over relay to match the band. Basically, when I switch from the 40 meter band to the 20 meter band on my radio, my Antenna Selector automatically changes over from my 40-meter rotatable dipole to my 20/17/15/12/10 meter Quad by energizing the correct change-over relay.
The Antenna Selector frequency-to-band data "memories" are contained in EEPROM so that they can be changed easily if you change antenna configurations.
Regards, Mike