7
7593L–AVR–09/12
AT90USB64/128
architecture is more code efficient while achieving throughputs up to ten times faster than con-
ventional CISC microcontrollers.
The Atmel AT90USB64/128 provides the following features: 64/128Kbytes of In-System Pro-
grammable Flash with Read-While-Write capabilities, 2K/4Kbytes EEPROM, 4K/8K bytes
SRAM, 48 general purpose I/O lines, 32 general purpose working registers, Real Time Counter
(RTC), four flexible Timer/Counters with compare modes and PWM, one USART, a byte ori-
ented 2-wire Serial Interface, a 8-channels, 10-bit ADC with optional differential input stage with
programmable gain, programmable Watchdog Timer with Internal Oscillator, an SPI serial port,
IEEE std. 1149.1 compliant JTAG test interface, also used for accessing the On-chip Debug sys-
tem and programming and six 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, dis-
abling all other chip functions until the next interrupt or Hardware Reset. In Power-save mode,
the asynchronous timer continues to run, allowing the user to maintain a timer base while the
rest of the device is sleeping. The ADC Noise Reduction mode stops the CPU and all I/O mod-
ules except Asynchronous Timer and ADC, to minimize switching noise during ADC
conversions. 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. In
Extended Standby mode, both the main Oscillator and the Asynchronous Timer continue to run.
The device is manufactured using the Atmel 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 pro-
gram 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. By combining an 8-bit RISC CPU with In-System Self-Programmable Flash on a
monolithic chip, the AT90USB64/128 is a powerful microcontroller that provides a highly flexible
and cost effective solution to many embedded control applications.
The AT90USB64/128 AVR is supported with a full suite of program and system development
tools including: C compilers, macro assemblers, program debugger/simulators, in-circuit emula-
tors, and evaluation kits.