Crack Chip PIC16F777 Firmware

Crack Chip PIC16F777 and extract firmware from microcontroller’s flash memory, reproduced program can be used to prepared cloned microprocessor PIC16F777 through reverse engineering microcontroller;

Crack Chip PIC16F777 and extract firmware from microcontroller's flash memory, reproduced program can be used to prepared cloned microprocessor PIC16F777 through reverse engineering microcontroller

Crack Chip PIC16F777 and extract firmware from microcontroller’s flash memory, reproduced program can be used to prepared cloned microprocessor PIC16F777 through reverse engineering microcontroller

Status Register:

The Status register contains the arithmetic status of the ALU, the Reset status and the bank select bits for data memory. The Status register can be the destination for any instruction, as with any other register. If the Status register is the destination for an instruction that affects the Z, DC or C bits, then the write to these three bits is disabled. These bits are set or cleared according to the device logic. Furthermore, the TO and PD bits are not writable, therefore, the result of an instruction with the Status register as destination may be different than intended.

For example, CLRF STATUS, will clear the upper three bits and set the Z bit. This leaves the Status register as 000u u1uu (where u = unchanged).

It is recommended, therefore, that only BCF, BSF, SWAPF and MOVWF instructions are used to alter the Status register because these instructions do not affect the Z, C or DC bits from the Status register. For other instructions not affecting any Status bits e, the result of an instruction with the Status register as destination may be different than intended.

The Program Counter (PC) is 13 bits wide. The low byte comes from the PCL register which is a readable and writable register. The upper bits (PC<12:8>) are not readable but are indirectly writable through the PCLATH register. On any Reset, the upper bits of the PC will be cleared. Figure 2-4 shows the two situations for the loading of the PC. The upper example in the figure shows how the PC is loaded on a write to PCL (PCLATH<4:0> → PCH). The lower example in the figure shows how the PC is loaded during a CALL or GOTO instruction (PCLATH<4:3> → PCH).

The stack operates as a circular buffer. This means that after the stack has been PUSHed eight times, the ninth push overwrites the value that was stored from the first push. The tenth push overwrites the second push (and so on).

PIC16F7X7 devices are capable of addressing a con- been PUSHed eight times, the ninth push overwrites the value that was stored from the first push. The tenth push overwrites the second push (and so on). tinuous 8K word block of program memory. The CALL and GOTO instructions provide only 11 bits of address to allow branching within any 2K program memory page.

When doing a CALL or GOTO instruction, the upper 2 bits of the address are provided by PCLATH<4:3>.

When doing a CALL or GOTO instruction, the user must fareast-font-family: 宋体;mso-bidi-font-family:Courier;color:black;mso-font kerning:0pt;mso-ansi-language: EN-US;mso-fareast-language:ZH-CN;mso-bidi-language:AR-SA’>GOTO instruction (PCLATH<4:3> → PCH).


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