PostHeaderIcon Microprocessor PIC18F4510 Eeprom Memory Breaking

Microprocessor PIC18F4510 Eeprom Memory Breaking

While the use of the BSR with an embedded 8-bit address allows users to address the entire range of data memory which can facilitate Microprocessor PIC18F4510 Eeprom Memory Breaking, it also means that the user must always ensure that the correct bank is selected. Otherwise, data may be read from or written to the wrong location.

This can be disastrous if a GPR is the intended target of an operation, but an SFR is written to instead. Verifying and/or changing the BSR for each read or write to data memory can become very inefficient.

To streamline access for the most commonly used data memory locations, the data memory is configured with an Access Bank, which allows users to access a mapped block of memory without specifying a BSR. The Access Bank consists of the first 128 bytes of memory (00h-7Fh) in Bank 0 and the last 128 bytes of memory (80h-FFh) in Block 15.

The lower half is known as the “Access RAM” and is composed of GPRs. This upper half is also where the device’s SFRs are mapped. These two areas are mapped contiguously in the Access Bank and can be addressed in a linear fashion by an 8-bit address.

The Access Bank is used by core PIC18F4510 instructions that include the Access RAM bit (the ‘a’ parameter in the instruction). When ‘a’ is equal to ‘1’, the instruction uses the BSR and the 8-bit address included in the opcode for the data memory address. When ‘a’ is ‘0’,

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