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Electronic locking system

  • US 4,785,425 A
  • Filed: 02/27/1987
  • Issued: 11/15/1988
  • Est. Priority Date: 02/27/1987
  • Status: Expired due to Fees
First Claim
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1. In an electronic locking system having a processor and an electrically erasable programmable read-only memory (EEPROM) and a random access memory (RAM) supported within said electronic locking system, said processor having address outputs electrically connected to address inputs of said EEPROM and of said RAM to address memory locations within said EEPROM and within said RAM, data inputs electrically connected to data inputs/outputs of said EEPROM and of said RAM to receive data from said EEPROM and from said RAM, and a high-impedence control input for transforming said address outputs of said processor to a high-impedence state and deactivating said processor inputs for isolating said processor, the improvement comprising:

  • a connector electrically connected to said address inputs of said EEPROM, said data inputs/outputs of said EEPROM, and said high-impedence control input of said processor, andEEPROM programming means electrically connected to said connector for activating said high-impedence control input of said processor to deactivate said inputs of said processor and render said address outputs of said processor to a high-impedence state during a programming operation, and for solely transmitting address information and data to said address inputs and data inputs/outputs of said EEPROM, respectively during said programming information to write data into said EEPROM, said RAM being unaffected during said programming of said EEPROM.

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