This application report discusses the design of non-invasive optical plethysmographyalso called as pulsoximeter using the MSP430FG437 Microcontroller (MCU). Thepulsoximeter consists of a peripheral probe combined with the MCU displaying theoxygen saturation and pulse rate on a LCD glass. The same sensor is used for bothheart-rate detection and pulsoximetering in this application. The probe is placed on aperipheral point of the body such as a finger tip, ear lobe or the nose. The probeincludes two light emitting diodes (LEDs), one in the visible red spectrum (660nm) andthe other in the infrared spectrum (940nm). The percentage of oxygen in the body isworked by measuring the intensity from each frequency of light after it transmitsthrough the body and then calculating the ratio between these two intensities.
標簽： Pulsoximeter Single-Chip Des
上傳時間： 2013-10-27
上傳用戶：黑漆漆
用戶程序示例教程 The Blinky project is a simple program for the LPC2138using Keil MCB2130 Microcontroller Board. It blinks the LEDs at speed according to the Potentiometer setting and prints the current seting to the Serial Port 1.In addition it generates a sine wave with an adjustable frequency on the speaker of the board.
上傳時間： 2014-12-27
上傳用戶：hongmo
FeaturesThe following standard features are provided.• Choice of RTOS scheduling policy1. Pre-emptive:Always runs the highest available task. Tasks of identical priorityshare CPU time (fully pre-emptive with round robin time slicing).2. Cooperative:Context switches only occur if a task blocks, or explicitly callstaskYIELD().• Co-routines (light weight tasks that utilise very little RAM).• Message queues• Semaphores [via macros]• Trace visualisation ability (requires more RAM)• Majority of source code common to all supported development tools• Wide range of ports and examples
上傳時間： 2013-10-13
上傳用戶：13162218709
匯編器在微處理器的驗證和應用中舉足輕重，如何設計通用的匯編器一直是研究的熱點之一。本文提出了一種開放式的匯編器系統設計思想，在匯編語言與機器語言間插入中間代碼CMDL（code mapping description language）語言，打破匯編語言與機器語言的直接映射關系，由此建立起一套描述匯編語言與機器語言的開放式映射體系。基于此開放式映射體系開發了一套匯編器系統，具有較高層次上的通用性和可移植性。【關鍵詞】指令集，CMDL，匯編器，開放式 Design of Retargetable Assembler System Liu Ling Feng Wen Nan Wang Ying Chun Jiang An Ping Ji Li Jiu IME of Peking University, 100871【摘要】An assembler plays a very important role in the field of microprocessor verifications and applications, thus how to build a retargetable assembler system has been a hotspot in this field for long time. This paper presents a new method about the retargetable assembler system design.It provides a kind of language CMDL, code mapping description language. During the process of assembling, assembler languages are firstly translated to CMDL, and then mapped to the machine codes. In an other word, CMDL is inserted between assembler languages and machine codes during the translation procedure. As a medium code, CMDL has a lot of features, such as high extraction, strong descript capabilities. It can describe almost all attributes of assembler languages. By breaking the direct mapping relationship between assembler languages and machine codes, the complexities of machine codes are hided to the users, therefore, the new retargetable assembler system has higher retargetable level by converting the mapping from assembler languages and machine codes to assembler languages and CMDL, and implementationof it becomes easier. Based on the new mapping system structure, a retargetable assemblersystem is developed. It proved the whole system has good retargetability and implantability.【關鍵詞】instruction set, symbol table, assembler, lexical analysis, retargetability
上傳時間： 2013-10-10
上傳用戶：meiguiweishi
The XL6003 regulator is fixed frequency PWM Boost (step-up) DC/DC converter, capable ofdriving 1050mA load current with excellent line and load regulation. The regulator is simple to use because it includes internal frequency compensation and a fixed-frequency oscillator so that it requires a minimum number of external components to work. The XL6003 could directly drive 5~10 3W LED units at VIN=12V.
上傳時間： 2013-11-07
上傳用戶：xy@1314
自動檢測80C51串行通訊中的波特率:本文介紹一種在80C51 串行通訊應用中自動檢測波特率的方法。按照經驗，程序起動后所接收到的第1 個字符用于測量波特率。這種方法可以不用設定難于記憶的開關，還可以免去在有關應用中使用多種不同波特率的煩惱。人們可以設想：一種可靠地實現自動波特檢測的方法是可能的，它無須嚴格限制可被確認的字符。問題是：在各種的條件下，如何可以在大量允許出現的字符中找出波特率定時間隔。顯然，最快捷的方法是檢測一個單獨位時間（single bit time），以確定接收波特率應該是多少。可是，在RS-232 模式下，許多ASCII 字符并不能測量出一個單獨位時間。對于大多數字符來說，只要波特率存在合理波動（這里的波特率是指標準波特率），從起始位到最后一位“可見”位的數據傳輸周期就會在一定范圍內發生變化。此外，許多系統采用8 位數據、無奇偶校驗的格式傳輸ASCII 字符。在這種格式里，普通ASCII 字節不會有MSB 設定，并且，UART總是先發送數據低位（LSB），后發送數據高位（MSB），我們總會看見數據的停止位。在下面的波特率檢測程序中，先等待串行通訊輸入管腳的起始信號（下降沿），然后起動定時器T0。在其后的串行數據的每一個上升沿，將定時器T0 的數值捕獲并保存。當定時器T0溢出時，其最后一次捕獲的數值即為從串行數據起始位到最后一個上升沿（我們假設是停止位）過程所持續的時間。
上傳時間： 2014-08-22
上傳用戶：dajin
Texas Instruments and its subsidiaries (TI) reserve the right to make changes to their productsor to discontinue any product or service without notice, and advise customers to obtain the latestversion of relevant information to verify, before placing orders, that information being relied onis current and complete. All products are sold subject to the terms and conditions of sale suppliedat the time of order acknowledgement, including those pertaining to warranty, patentinfringement, and limitation of liability.
標簽： Assembly Language C6000 320C
上傳時間： 2013-11-12
上傳用戶：chens000
The PCA9534 is a 16-pin CMOS device that provide 8 bits of General Purpose parallel Input/Output (GPIO) expansion for I2C-bus/SMBus applications and was developed to enhance the NXP Semiconductors family of I2C-bus I/O expanders. The improvements include higher drive capability, 5 V I/O tolerance, lower supply current, individual I/O configuration, 400 kHz clock frequency, and smaller packaging. I/O expanders provide a simple solution when additional I/O is needed for ACPI power switches, sensors, push buttons, LEDs, fans, etc.
上傳時間： 2013-10-10
上傳用戶：inwins
The PCA9540B is a 1-of-2 bidirectional translating multiplexer, controlled via the I2C-bus.The SCL/SDA upstream pair fans out to two SCx/SDx downstream pairs, or channels.Only one SCx/SDx channel is selected at a time, determined by the contents of theprogrammable control register.
上傳時間： 2014-12-28
上傳用戶：nshark
The PCA9541 is a 2-to-1 I2C-bus master selector designed for high reliability dual masterI2C-bus applications where system operation is required, even when one master fails orthe controller card is removed for maintenance. The two masters (for example, primaryand back-up) are located on separate I2C-buses that connect to the same downstreamI2C-bus slave devices. I2C-bus commands are sent by either I2C-bus master and are usedto select one master at a time. Either master at any time can gain control of the slavedevices if the other master is disabled or removed from the system. The failed master isisolated from the system and will not affect communication between the on-line masterand the slave devices on the downstream I2C-bus.
上傳時間： 2013-10-09
上傳用戶：3294322651
