Crack Microcontroller PIC16F727 Program

Crack Microcontroller PIC16F727 Program from its memory cell which include flash and eeprom, then copy the firmware to blank Microcontroller to provide the same functions;

Crack Microcontroller PIC16F727 Program

Crack Microcontroller PIC16F727 Program

The Baud Rate Generator (BRG) is an 8-bit timer that is dedicated to the support of both the asynchronous and synchronous AUSART operation. The SPBRG register determines the period of the free running baud rate timer. In Asynchronous mode the multiplier of the baud rate period is determined by the BRGH bit of the TXSTA register. In Synchronous mode, the BRGH bit is ignored.

Table 16-3 contains the formulas for determining the baud rate. Example 16-1 provides a sample calculation for determining the baud rate and baud rate error. Typical baud rates and error values for various asynchronous modes have been computed for your convenience and are shown in Table 16-3. It may be advantageous to use the high baud rate (BRGH = 1), to reduce the baud rate error.

Writing a new value to the SPBRG register causes the BRG timer to be reset (or cleared). This ensures that the BRG does not wait for a timer overflow before outputting the new baud rate. Synchronous serial communications are typically used in systems with a single master and one or more slaves. The master device contains the necessary circuitry for baud rate generation and supplies the clock for all devices in the system.

Slave devices can take advantage of the master clock by eliminating the internal clock generation circuitry. There are two signal lines in Synchronous mode: a bidirectional data line and a clock line. Slaves use the external clock supplied by the master to shift the serial data into and out of their respective receive and transmit shift registers.

Since the data line is bidirectional, synchronous operation is half-duplex only. Half-duplex refers to the fact that master and slave devices can receive and transmit data but not both simultaneously. The AUSART can operate as either a master or slave device.

Data is transferred out of the device on the RX/DT pin.

The RX/DT and TX/CK pin output drivers are automatically enabled when the AUSART is configured for synchronous master transmit operation. A transmission is initiated by writing a character to the TXREG register. If the TSR still contains all or part of a previous character, the new character data is held in the TXREG until the last bit of the previous character has been transmitted.

If this is the first character, or the previous character has been completely flushed from the TSR, the data in the TXREG is immediately transferred to the TSR. The transmission of the character commences immediately following the transfer of the data to the TSR from the TXREG.

Each data bit changes on the leading edge of the master clock and remains valid until the subsequent leading clock edge. Synchronous data transfers use a separate clock line, which is synchronous with the data. A device configured as a master transmits the clock on the TX/CK line.

The TX/CK pin output driver is automatically enabled when the AUSART is configured for synchronous transmit or receive operation. Serial data bits change on the leading edge to ensure they are valid at the trailing edge of each clock. One clock cycle is generated for each data bit. Only as many clock cycles are generated as there are data bits.

Data is received at the RX/DT pin. The RX/DT pin output driver is automatically disabled when the AUSART is configured for synchronous master receive operation. In Synchronous mode, reception is enabled by setting either the Single Receive Enable bit (SREN of the RCSTA register) or the Continuous Receive Enable bit (CREN of the RCSTA register).

When SREN is set and CREN is clear, only as many clock cycles are generated as there are data bits in a single character. The SREN bit is automatically cleared at the completion of one character. When CREN is set, clocks are continuously generated until CREN is cleared. If CREN is cleared in the middle of a character the CK clock stops immediately and the partial character is discarded. If SREN and CREN are both set, then SREN is cleared at the completion of the first character and CREN takes precedence.


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