The AVR core combines a rich instruction set with 32 general purpose working registers which will provide facilitation to Extract AVR Microcontroller ATmega8515. All the 32 registers are directly connected to the Arithmetic Logic Unit (ALU), allowing t wo independent registers to be accessed in one single instruction executed in one clock cycle. The resulting architecture is more code efficient while achieving throughputs up toten times faster than conventional CISC microcontrollers.
The ATmega8515 provides the following features: 8K bytes of In-System Programmable Flash with Read-While-Write capabilities, 512 bytes EEPROM, 512 bytes SRAM, an External memory interface, 35 general purpose I/O lines, 32 general purpose working registers, two flexible Timer/Counters with compare modes, Internal and External interrupts, a Serial Programmable USART, a programmable Watchdog Timer with internal Oscillator, a SPI serial port, and three software selectable power saving modes.
The Idle mode stops the CPU while allowing the SRAM, Timer/Counters, SPI port, and Interrupt system to continue functioning. The Power-down mode saves the Register contents but freezes the Oscillator, disabling all other chip functions until the next interrupt or hardware reset.
In Standby mode, the crystal/resonator Oscillator is running while the rest of the device is sleeping. This allows very fast start-up combined with low-power consumption.
The device is manufactured using Atmel’s high density nonvolatile memory technology.
The On-chip ISP Flash allows the Program memory to be reprogrammed In-System through an SPI serial interface, by a conventional nonvolatile memory programmer, or by an On-chip Boot program running on the AVR core. The boot program can use any interface to download the application program in the Application Flash memory.
Software in the Boot Flash section will continue to run while the Application Flash section is updated, providing true Read-While-Write operation to recover MCU code. By combining an 8-bit RISC CPU with In-System Self-programmable Flash on a monolithic chip, the Atmel ATmega8515 is a powerful microcontroller that provides a highly flexible and cost effective solution to many embedded control applications.
The ATmega8515 is supported with a full suite of program and system development tools including: C Compilers, Macro assemblers, Program debugger/simulators, In-circuit Emulators, and Evaluation kits. Typical values contained in this datasheet are based on simulations and characterization of other AVR microcontrollers manufactured on the same process technology. Min and Max values will be available after the device is characterized.
The timed sequence for changing the Watchdog Time-out period is disabled. See “Timed Sequences for Changing the Configuration of the Watchdog Timer” on page 52 for details. The double buffering of the USART Receive Registers is disabled. See “AVR USART vs. AVR UART – Compatibility” on page 135 for details. PORTE(2:1) will be set as output, and PORTE0 will be set as input.