ELECTRICALLY ERASABLE AND REPROGRAMMABLE, NONVOLATILE INTEGRATED STORAGE DEVICE WITH IN-SYSTEM PROGRAMMING AND VERIFICATION (ISPAV) CAPABILITIES FOR SUPPORTING IN-SYSTEM RECONFIGURING OF PLD'S

摘要

An in-system programmable and verifiable (ISPAV) configuration restoring device (CROP device) has an Electrically Erasable and reprogrammable, NonVolatile Integrated Storage array (e.g., a FLASH EE_NVIS array) into which configuration instructions may be written for later readout during configuration restoration of a Programmable Logic Device (PLD) where the PLD has a volatile configuration memory. The volatile PLD may be an FPGA or a CPLD. The ISPAV CROP device includes a shared shift register through which configuration instructions read from the EE_NVIS array are serially shifted out to a to-be-configured PLD. The shared shift register is also used for loading new configuration instructions into the EE_NVIS array by way of a 4-wire interface such as JTAG and also for verifying proper writing of these instructions into the EE_NVIS array.