Fast scanning radio receiver with frequency data base management by

Abstract

A scanning receiver includes an Electrically Erasable Programmable Read Only Memory (EEPROM) as massive nonvolatile storage for frequency control words. The receiver includes a microprocessor based receiver controller which executes data base management routines to manipulate the data base which is partitioned into scan banks of multiple frequency selection words and search banks of two limit frequency selection words. The software includes routines which can add or delete frequencies, change banks, control the scanning order of the banks, provide priority to a selected bank, and other functions. The EEPROM, to maintain its longevity, is only written to if bank of frequencies is changed while in the RAM of the receiver controller. After a bank of frequencies is changed in RAM, it is sorted in descending order so that a rapid slewing of the local oscillator frequency can be implemented in a single direction. The receiver controller further includes a communication routine and interface circuitry which allows the receiver to communicate with a remote processor, preferably a personal computer system. The remote processor executes an application program which allows the manipulation of a data base which emulates that of the scanning receiver stored in the EEPROM. Application routines allow the direct control of the receiver from the remote processor and the manipulation of the EEPROM data base including downloading or uploading bank data. The remote processor further controls an auto-frequency mode where frequencies which are found during the search mode of the receiver are uploaded to a file of the remote processor and stored for further examination.