Description
The AT91M40400 is a member of the Atmel AT91 16/32-bit Microcontroller family which is based on the ARM7TDMI processor core. This processor has a high-performance 32-bit RISC architecture with a high-density 16-bit instruction set and very low power consumption. In addition, a large number of internally banked registers result in very fast exception handling, making the device ideal for real-time control applications.

Features
• Incorporates the ARM7TDMI™ ARM® Thumb® Processor Core
    – High-performance 32-bit RISC Architecture
    – High-density 16-bit Instruction Set
    – Leader in MIPS/Watt
    – Embedded ICE (In Circuit Emulation)
• 4K Bytes Internal RAM
• Fully Programmable External Bus Interface (EBI)
    – Maximum External Address Space of 64M Bytes
    – Up to 8 Chip Selects
    – Software Programmable 8/16-bit External Databus
• 8-level Priority, Individually Maskable, Vectored Interrupt Controller
    – 4 External interrupts, including a High-priority Low-latency Interrupt Request
• 32 Programmable I/O Lines
• 3-channel 16-bit Timer/Counter
    – 3 External Clock Inputs
    – 2 Multi-purpose I/O Pins per Channel
• 2 USARTs
    – 2 Dedicated Peripheral Data Controller (PDC) Channels per USART
• Programmable Watchdog Timer
• Low-power Idle Mode
• Fully Static Operation: 0 Hz to 33 MHz
• 2.7V to 3.6V Operating Range
• Available in a 100-lead TQFP Package