[LUMINARY MICRO] Architectural Overview The Luminary Micro Stellaris® family of microcontrollers—the first ARM® Cortex™-M3 based controllers—brings high-performance 32-bit computing to cost-sensitive embedded microcontroller applications. These pioneering parts deliver customers 32-bit performance at a cost equivalent to legacy 8- and 16-bit devices, all in a package with a small footprint. Product Features The LM3S817 microcontroller includes the following product features: ■ 32-Bit RISC Performance – 32-bit ARM® Cortex™-M3 v7M architecture optimized for small-footprint embedded applications – System timer (SysTick) provides a simple, 24-bit clear-on-write, decrementing, wrap-on-zero counter with a flexible control mechanism – Thumb®-compatible Thumb-2-only instruction set processor core for high code density – 50-MHz operation – Hardware-division and single-cycle-multiplication – Integrated Nested Vectored Interrupt Controller (NVIC) providing deterministic interrupt handling – 26 interrupts with eight priority levels – Memory protection unit (MPU) provides a privileged mode for protected operating system functionality – Unaligned data access, enabling data to be efficiently packed into memory – Atomic bit manipulation (bit-banding) delivers maximum memory utilization and streamlined peripheral control ■ Internal Memory – 64-KB single-cycle flash • User-managed flash block protection on a 2-KB block basis • User-managed flash data programming • User-defined and managed flash-protection block – 8-KB single-cycle SRAM ■ General-Purpose Timers – Three timers, each of which can be configured: as a single 32-bit timer, as two 16-bit timers, or to initiate an ADC event – 32-bit Timer modes: • Programmable one-shot timer • Programmable periodic timer • Real-Time Clock when using an external 32.768-KHz clock as the input • User-enabled stalling in periodic and one-shot mode when the controller asserts the CPU Halt flag during debug • ADC event trigger – 16-bit Timer modes: • General-purpose timer function with an 8-bit prescaler • Programmable one-shot timer • Programmable periodic timer • User-enabled stalling when the controller asserts CPU Halt flag during debug • ADC event trigger – 16-bit Input Capture modes: • Input edge count capture • Input edge time capture – 16-bit PWM mode: • Simple PWM mode with software-programmable output inversion of the PWM signal ■ ARM FiRM-compliant Watchdog Timer – 32-bit down counter with a programmable load register – Separate watchdog clock with an enable – Programmable interrupt generation logic with interrupt masking – Lock register protection from runaway software – Reset generation logic with an enable/disable – User-enabled stalling when the controller asserts the CPU Halt flag during debug ■ Synchronous Serial Interface (SSI) – Master or slave operation – Programmable clock bit rate and prescale – Separate transmit and receive FIFOs, 16 bits wide, 8 locations deep – Programmable interface operation for Freescale SPI, MICROWIRE, or Texas Instruments synchronous serial interfaces – Programmable data frame size from 4 to 16 bits – Internal loopback test mode for diagnostic/debug testing ■ UART – Two fully programmable 16C550-type UARTs – Separate 16x8 transmit (TX) and 16x12 receive (RX) FIFOs to reduce CPU interrupt service loading – Programmable baud-rate generator with fractional divider – Programmable FIFO length, including 1-byte deep operation providing conventional double-buffered interface – FIFO trigger levels of 1/8, 1/4, 1/2, 3/4, and 7/8 – Standard asynchronous communication bits for start, stop, and parity – False-start-bit detection – Line-break generation and detection (Continue ...)
|