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9 Reasons to Love STR910F

(STR910F系列微控制器受到大家喜欢的9个原因）

1. Ethernet!
2. Very large SRAM and dual-bank Flash memories
3. 96 MIPS peak performance from ARM9E core
4. Efficient DMA and rapid data flow
5. 1uA real-time clock with tamper detection
6. Connectivity, excellent selection
7. Minimal external components required
8. Power management
9. Extensive tools and firmware library support

Reason #1
Ethernet

  1. Connects the application to local network or Intranet
    - Connectivity adds value to the end product and demand is surging
  2. Ethernet MAC has MII interface to external PHY
    - Customer can choose the media: copper, wireless, fiber, etc
  3. Dedicated DMA between MAC and SRAM
    - High DMA transfer rate to/from SRAM offloads the CPU
    4. STR910F is the world’s first Ethernet-enabled ARM9 Flash MCU family

Reason #2
Very Large SRAM and Flash Memories

  1. Largest SRAM in market segment at 96KB
    - Optionally battery back up at only 5μA typical
    - Extra large size RTOS, TCP/IP stack, Ethernet and USB buffers
  2. Dual Bank Flash Memories up to 544 KB
    - Banks for In-Application Programming or EEPROM emulation
    - 100K min erase cycles, 20 year data retention
    - Extra large size for: RTOS plus Application, TCP/IP,
    HTML pages, data recording, self-diagnostic code
    Very Large SRAM and Flash Memories

No other Flash ARM MCU has battery backup capability for SRAM

Reason #3
96 MIPS Peak Performance from an ARM9E Core

  1. Best peak performance in market segment
    - Sequential instructions at 96MHz directly from STR910F burst Flash

  2. ARM9E core: Separate internal paths for Instructions and Data
    - Simultaneous access of code and data. Not possible with ARM7TDMI
    - ARM’s Tightly-Coupled Memory interface for fast access

  3. ARM9E core supports single-cycle DSP instructions
    - Performs 64-point FFT in only 32 usec, 1024-point in 787 usec
    - Performs 64-point FFT in only 32 usec, 1024-point in 787 usec

STR910 can eliminate the need for separate DSP and control processors

Reason #4
Efficient DMA and Rapid Data Flow

  1. Direct path to SRAM through arbiter, guarantees alternating access

  2. 9 ARM primecell DMA channels, full function “linked-list” features

Offloads CPU so it can focus on real-time control tasks

Reason #5
1μA Real-time Clock with Tamper Detection

  1. RTC draws less than 1μA from battery across entire temp range!

  2. 30+ year battery life from typical coin cell at room temperature

  3. Records time of Tamper event and cuts power to SRAM to destroy contents if desired

  4. Features found typically in external RTC devices ($0.50 to $1.00)

Tamper detection, time-stamping and ultra-low current are exclusive STR910F benefits that draw on ST’s leadership in RTC/supervisors

Reason #6
Excellent Connectivity

  1. Communication
    - USB-FS device, CAN2.0B, UARTs , SPI, I2C…. plus Ethernet
    - Up to 80 GPIOs, Individual Set/Clear, 5V tolerant

  2. Analog: 8-channel ADC, 10-bit, 2μsec conversion

  3. External Static Memory Bus: 8-bit or 16-bit data

  4. Debug: ARM’s ETM9 real-time trace interface

Excellent for communication gateways, such as Ethernet-to-USB, Ethernet-to-CAN

Reason #7
Minimal External Components Required

  1. Built in Supervisor reduces need for external components
    - Filtered reset input, Power-On reset, Low-Voltage Detect, Brown-Out Detect, Watchdog Timer

  2. One main crystal drives entire system (with help from PLL)
    - Inexpensive 25MHz crystal drives CPU system, Ethernet, USB, and all peripherals
    - Optional 32kHz crystal needed additionally for RTC

More inside means less outside!

Reason #8
Power Management

  1. Dynamically balance performance vs. power consumption
    - Adjust individual clocks to CPU and peripherals

  2. Run Mode
    - Typical average consumption:1.3mA per MHz of CPU operation
    - Run-Slow at 32KHz clock for typical current draw of only 700μA

  3. Idle mode
    - Typical average consumption: 0.7mA per MHz of CPU operation

  4. Sleep mode: Device quiescent with RTC running
    - Typical current consumption of 55μA

  5. Battery Backup when main power is off
    - Backup RTC and SRAM: 5μA at room temperature, 85μA max
    - Backup only RTC: 0.3μA at room temperature, 0.9μA max

Lowest RTC current for Flash ARM-based MCUs

Reason #9
Extensive Tools and Firmware Library Support

  1. 5 Development kits
    - Starter kits from Hitex, IAR, Keil, Raisonance
    - Everything needed to start a design, right out of the box
    - All based on ST HAL library so there’s commonality and less support needed
    - ST evaluation board available for in-depth hardware evaluation

  2. Hardware Abstraction Layer (HAL) Library
    - Common low-level firmware drivers supplied freely from ST web
    - Prevents customer from having to study datasheet in depth
    - Prevents errors and tech questions because HAL library is certified by ST
    - Standard ANSI-C, use with any compiler supporting STR910F

Spend more time designing your product and less time getting started