Replicate Locked MCU AT89C1051 Eeprom Data
Replicate Locked MCU AT89C1051 Eeprom Data
Replicate Locked MCU AT89C1051 Eeprom Data needs to disable its internal protection mechanism and then read out the data from eeprom directly, hereby we present the critical features of the AT89C1051:
The AT89C1051 is a low-voltage, high-performance CMOS 8-bit microcomputer with 1K byte of Flash programmable and erasable read only memory (PEROM).
The device is manufactured using Atmel’s high density nonvolatile memory technology and is compatible with the industry standard MCS-51™ instruction set. By combining a versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89C1051 is a pow-with 1K Byte Flash.
AT89C1051 uerful microcomputer which provides a highly flexible and cost effective solution to many embedded control applications. The AT89C1051 provides the following standard features: 1K Byte of Flash, 64 bytes of RAM, 15 I/O lines, one 16-bit timer/counter, a three vector two-level interrupt architecture, a precision analog comparator, on-chip oscillator and clock circuitry.
In addition, the AT89C1051 is designed with static logic for operation down to zero frequency and supports two software selectable power saving modes. The Idle Mode stops the CPU while allowing the RAM, timer/counters, serial port and interrupt system to continue functioning.
The Power Down Mode saves the RAM contents but freezes the oscillator disabling all other chip functions until the next hardware reset before Replicate Locked MCU AT89C1051 Eeprom Data.
Port 1
Port 1 is an 8-bit bidirectional I/O port. Port pins P1.2 to P1.7 provide internal pullups. P1.0 and P1.1 require external pullups. P1.0 and P1.1 also serve as the positive input (AIN0) and the negative input (AIN1), respectively, of the on-chip precision analog comparator. The Port 1 output buffers can sink 20 mA and can drive LED displays directly.
When 1s are written to Port 1 pins, they can be used as inputs. When pins P1.2 to P1.7 are used as inputs and are externally pulled low, they will source current (IIL) because of the internal pullups.
Port 1 also receives eeprom data data during Flash programming and verification.
Port 3
Port 3 pins P3.0 to P3.5, P3.7 are seven bidirectional I/O pins with internal pullups. P3.6 is hard-wired as an input to the output of the on-chip comparator and is not accessible as a general purpose I/O pin. The Port 3 output buffers can sink 20 mA. When 1s are written to Port 3 pins they are pulled high by the internal pullups and can be used as inputs. As inputs, Port 3 pins that are externally being pulled low will source current (IIL) because of the pullups.
Port 3 also serves the functions of various special features of the AT89C1051 as listed below Port 3 also receives some control signals for Flash programming and verification. XTAL1 and XTAL2 are the input and output, respectively, of an inverting amplifier which can be configured for use as an on-chip oscillator.
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.
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.