Archive for November, 2017

PostHeaderIcon Break Chip ATMEGA861P Code

We can Break chip ATMEGA861P code, please view the chip ATMEGA861P features for your reference:
Timer 2 is selected as the baud rate generator by setting TCLK and/or RCLK in T2CON (Table 2). Note that the baud rates for transmit and receive can be different if Timer 2 is used for the receiver or transmitter and Timer 1 is used for the other function. Setting RCLK and/or TCLK puts Timer 2 into its baud rate generator mode, as shown in Figure 4 when Break Chip ATMEGA861P Code.
The baud rate generator mode is similar to the auto-reload mode, in that a rollover in TH2 causes the Timer 2 registers to be reloaded with the 16 bit value in registers RCAP2H and RCAP2L, which are preset by code.
The baud rates in Modes 1 and 3 are determined by Timer 2’s overflow rate according to the following equation. The Timer can be configured for either timer or counter operation. In most applications, it is configured for timer operation (CP/T2 = 0) before Break Chip ATMEGA861P Code.
The timer operation is different for Timer 2 when it is used as a baud rate generator. Normally, as a timer, it increments every machine cycle (at 1/12 the oscillator frequency). As a baud rate generator, however, it increments every state time (at 1/2 the oscillator fre-quency).
The baud rate formula is given below. where (RCAP2H, RCAP2L) is the content of RCAP2H and RCAP2L taken as a 16 bit unsigned integer. Timer 2 as a baud rate generator is shown in Figure 4 when Break chip code.
This figure is valid only if RCLK or TCLK = 1 in T2CON. Note that a rollover in TH2 does not set TF2 and will not generate an interrupt. Note too, that if EXEN2 is set, a 1-to-0 transition in T2EX will set EXF2 but will not cause a reload from (RCAP2H, RCAP2L) to (TH2, TL2) if Break Chip ATMEGA861P Code.
Thus when Timer 2 is in use as a baud rate generator, T2EX can be used as an extra external interrupt. Note that when Timer 2 is running (TR2 = 1) as a timer in the baud rate generator mode, TH2 or TL2 should not be read from or written to.
Under these conditions, the Timer is incremented every state time, and the results of a read or write may not be accurate. The RCAP2 registers may be read but should not be written to, because a write might overlap a reload and cause write and/or reload errors. The timer should be turned off (clear TR2) before accessing the Timer 2 or RCAP2 registers after Break IC.

PostHeaderIcon Break MCU ATMEGA861V Flash

We can break MCU ATMEGA861V flash, please view the MCU ATMEGA861V features for your reference:

A 50% duty cycle clock can be programmed to come out on P1.0, as shown in Figure 5. This pin, besides being a regular I/0 pin, has two alternate functions. It can be programmed to input the external clock for Timer/Counter 2 or to output a 50% duty cycle clock ranging from 61 Hz to 4 MHz at a 16 MHz operating frequency when break MCU flash.
To configure the Timer/Counter 2 as a clock generator, bit C/T2 (T2CON.1) must be cleared and bit T2OE (T2MOD.1) must be set. Bit TR2 (T2CON.2) starts and stops the timer if break MCU flash.
The clock-out frequency depends on the oscillator frequency and the reload value of Timer 2 capture registers (RCAP2H, RCAP2L), as shown in the following equation before break MCU flash.
In the clock-out mode, Timer 2 rollovers will not generate an interrupt. This behavior is similar to when Timer 2 is used as a baud-rate generator. It is possible to use Timer 2 as a baud-rate generator and a clock generator simultaneously after break MCU flash.
Note, however, that the baud-rate and clock-out frequencies cannot be determined independently from one another since they both use RCAP2H and RCAP2L when break MCU flash.
The UART in the AT89S53 operates the same way as the UART in the ATMEGA861V. For fur- ther information, see the October 1995 MMCUrocontroller Data Book, page 2-49, section titled, “Serial Interface.” if break MCU flash
The serial peripheral interface (SPI) allows high-speed synchronous data transfer between the ATMEGA861V and peripheral devMCUes or between several ATMEGA861V devMCUes before break MCU flash.
The AT89S53 SPI features include the following:
Full-Duplex, 3-Wire Synchronous Data Transfer
Master or Slave Operation
1.5-MHz Bit Frequency (max.)
LSB First or MSB First Data Transfer
Four Programmable Bit Rates after break MCU flash
End of Transmission Interrupt Flag
Write Collision Flag Protection
Wakeup from Idle Mode (Slave Mode Only)

PostHeaderIcon Recover Microprocessor ATMEGA640V Firmware

We can recover microprocessor ATMEGA640V firmware, please view the microprocessor ATMEGA640V features for your reference:
XTAL1 and XTAL2 are the input and output, respectively, of an inverting amplifier that can be configured for use as an on-chip oscillator, as shown in Figure 11. Either a quartz crystal or ceramic resonator may be used.
To drive the device from an external clock source, XTAL2 should be left unconnected while XTAL1 is driven, as shown in Figure 12.
There are no requirements on the duty cycle of the external clock signal, since the input to the internal clocking circuitry is through a divide-by-two flip-flop, but minimum and maximum voltage high and low time specifications must be observed if Recover Microprocessor ATMEGA640V Firmware.
In idle mode, the CPU puts itself to sleep while all the on-chip peripherals remain active. The mode is invoked by software. The content of the on-chip RAM and all the special functions registers remain unchanged during this mode. The idle mode can be terminated by any enabled interrupt or by a hardware reset.
Note that when idle mode is terminated by a hardware reset, the device normally resumes firmware execution from where it left off, up to two machine cycles before the internal reset algorithm takes control. On-chip hardware inhibits access to internal RAM in this event, but access to the port pins is not inhibited.
To eliminate the possibility of an unexpected write to a port pin when idle mode is terminated by a reset, the instruction following the one that invokes idle mode should not write to a port pin or to external memory when Recover Microprocessor ATMEGA640V Firmware.
In the power down mode, the oscillator is stopped and the instruction that invokes power down is the last instruction executed. The on-chip RAM and Special Function Registers retain their values until the power down mode is terminated.
Exit from power down can be initiated either by a hardware reset or by an enabled external interrupt. Reset redefines the SFRs but does not change the on-chip RAM. The reset should not be activated before VCC is restored to its normal operating level and must be held active long enough to allow the oscillator to restart and stabilize before Recover Microprocessor ATMEGA640V Firmware.
To exit power down via an interrupt, the external interrupt must be enabled as level sensitive before entering power down. The interrupt service routine starts at 16 ms (nominal) after the enabled interrupt pin is activated after RECOVER MCU.