单片机是单片微型计算机(SingleChipMicrocomputer)的简称,它的内部包含有计算机的基本功能部件:中央处理器(CPU)、存储器、定时/计数器、各种串/并行I/O接口电路等。因此,单片机只需要和适当的软件及外部设备相结合,便可成为一个单片机控制系统。近年来,由于半导体技术和工艺的快速发展,以及针对各行各业的实际应用需要,单片机的开发方面又出现了许多新的技术。SOC(System On Chip,片上系统)等名词日益被人们所熟悉和关注。
上传时间: 2013-10-10
上传用户:zhang97080564
NXP Semiconductor designed the LPC2400 microcontrollers around a 16-bit/32-bitARM7TDMI-S CPU core with real-time debug interfaces that include both JTAG andembedded Trace. The LPC2400 microcontrollers have 512 kB of on-Chip high-speedFlash memory. This Flash memory includes a special 128-bit wide memory interface andaccelerator architecture that enables the CPU to execute sequential instructions fromFlash memory at the maximum 72 MHz system clock rate. This feature is available onlyon the LPC2000 ARM Microcontroller family of products. The LPC2400 can execute both32-bit ARM and 16-bit Thumb instructions. Support for the two Instruction Sets meansEngineers can choose to optimize their application for either performance or code size atthe sub-routine level. When the core executes instructions in Thumb state it can reducecode size by more than 30 % with only a small loss in performance while executinginstructions in ARM state maximizes core performance.
上传时间: 2013-11-15
上传用户:zouxinwang
The main oscillator allows either a crystal or single-ended input clock signal. Cost-sensitiveapplications typically use an external crystal with the on-Chip oscillator circuit since it is the mostcost-effective solution. It is also possible to use the internal oscillator to clock the device after theboot process has completed.
标签: Stellaris Clocking Options for
上传时间: 2013-10-14
上传用户:pol123
The C500 microcontroller family usually provides only one on-Chip synchronous serialchannel (SSC). If a second SSC is required, an emulation of the missing interface mayhelp to avoid an external hardware solution with additional electronic components.The solution presented in this paper and in the attached source files emulates the mostimportant SSC functions by using optimized SW routines with a performance up to 25KBaud in Slave Mode with half duplex transmission and an overhead less than 60% atSAB C513 with 12 MHz. Due to the implementation in C this performance is not the limitof the chip. A pure implementation in assembler will result in a strong reduction of theCPU load and therefore increase the maximum speed of the interface. In addition,microcontrollers like the SAB C505 will speed up the interface by a factor of two becauseof an optimized architecture compared with the SAB C513.Moreover, this solution lays stress on using as few on-Chip hardware resources aspossible. A more excessive consumption of those resources will result in a highermaximum speed of the emulated interface.Due to the restricted performance of an 8 bit microcontroller a pin compatible solution isprovided only; the internal register based programming interface is replaced by a set ofsubroutine calls.The attached source files also contain a test shell, which demonstrates how to exchangeinformation between an on-Chip HW-SSC and the emulated SW-SSC via 5 external wiresin different operation modes. It is based on the SAB C513 (Siemens 8 bit microcontroller).A table with load measurements is presented to give an indication for the fraction of CPUperformance required by software for emulating the SSC.
标签: synchronous Emulating serial
上传时间: 2014-01-31
上传用户:z1191176801
The P90CL301 is a highly integrated 16/32 bit micro-controller especially suitable for applications requiring lowvoltage and low power consumption. It is fully software compatible with the 68000. Furthermore, it provides bothstandard as well as advanced peripheral functions on-Chip.One of these peripheral functions is the I2C bus. This report describes worked-out driver software (written in C) toprogram the P90CL301 I2C interface. It also contains interface software routines offering the user a quick start inwriting a complete I2C system application.
上传时间: 2014-01-06
上传用户:气温达上千万的
The XA-S3 is a member of Philips Semiconductors’ XA (eXtended Architecture) family of high performance 16-bit single-chip Microcontrollers. The XA-S3 combines many powerful peripherals on one chip. Therefore, it is suited for general multipurpose high performance embedded control functions.One of the on-Chip peripherals is the I2C bus interface. This report describes worked-out driver software (written in C) to program / use the I2C interface of the XA-S3. The driver software, together with a demo program and interface software routines offer the user a quick start in writing a complete I2C - XAS3 system application.
上传时间: 2013-11-10
上传用户:liaofamous
用C51写的普通拼音输入法源程序代码:原作使用了一个二维数组用以查表,我认为这样比较的浪费空间,而且每个字表的索引地址要手工输入,效率不高。所以我用结构体将其改写了一下。就是大家现在看到的这个。 因为代码比较的大,共有6,000多汉字,这样就得要12,000 byte来存放GB内码,所以也是没办法的.编译结果约为3000h,因为大部分是索引表,代码优化几乎无效。 在Keil C里仿真芯片选用的是华邦的W77E58,它有32k ROM, 256B on-Chip RAM, 1K on-Chip SRAM (用DPTR1指针寻址,相当于有1K的片上xdata)。条件有限,没有上片试验,仿真而已。 打算将其移植到AVR上,但CodeAVRC与IAR EC++在结构体、指针的定义使用上似乎与C51不太一样,现在还未搞定。还希望在这方面有经验的网友能给予指导。 #include<stdio.h> char * py_ime(char *); void main(void){ while(1) { char input_string[]="yI"; xdata char chinese_string[255]; sprintf(chinese_string,"%s",py_ime(input_string)); }}
上传时间: 2013-10-30
上传用户:cainaifa
PK51是为8051系列单片机所设计的开发工具,支持所有8051系列衍生产品,,支持带扩展存储器和扩展指令集(例如Dallas390/5240/400,Philips 51MX,Analog Devices MicroConverters)的新设备,以及支持很多公司的一流的设备和IP内核,比如Analog Devices, Atmel, Cypress Semiconductor, Dallas Semiconductor, Goal, Hynix, Infineon, Intel, NXP(founded by Philips), OKI, Silicon Labs,SMSC, STMicroeleectronics,Synopsis, TDK, Temic, Texas Instruments,Winbond等。通过PK51专业级开发工具,可以轻松地了解8051的on-Chip peripherals与及其它关键特性。
上传时间: 2013-10-09
上传用户:1109003457
The AT89C52 is a low-power, high-performance CMOS 8-bit microcomputer with 8Kbytes of Flash programmable and erasable read only memory (PEROM). The deviceis manufactured using Atmel’s high-density nonvolatile memory technology and iscompatible with the industry-standard 80C51 and 80C52 instruction set and pinout.The on-Chip Flash allows the program memory to be reprogrammed in-system or by aconventional nonvolatile memory programmer. By combining a versatile 8-bit CPUwith Flash on a monolithic chip, the Atmel AT89C52 is a powerful microcomputerwhich provides a highly-flexible and cost-effective solution to many embedded controlapplications.
上传时间: 2013-11-10
上传用户:1427796291
The Tri-Mode Ethernet MAC (TEMAC) UltraController-II module is a minimal footprint,embedded network processing engine based on the PowerPC™ 405 (PPC405) processor coreand the TEMAC core embedded within a Virtex™-4 FX Platform FPGA. The TEMACUltraController-II module connects to an external PHY through Gigabit Media IndependentInterface (GMII) and Management Data Input/Output (MDIO) interfaces and supports tri-mode(10/100/1000 Mb/s) Ethernet. Software running from the processor cache reads and writesthrough an on-Chip Memory (OCM) interface to two FIFOs that act as buffers between thedifferent clock domains of the PPC405 OCM and the TEMAC.
上传时间: 2013-10-26
上传用户:yuzsu