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 solution presented in this paper and in the attached source files emulates the mostimportant SSC functions by using SW routines implemented in C. The code is focused onthe SAB C513, but will fit to all C500 derivatives.Beyond the low level software drivers a test shell is delivered. This shell allows a quicktest of the software drivers by an emulator or a starter kit demo board.
上传时间： 2013-11-24
上传用户：363186
This application note shows how to write an Inter Integrated Circuit bus driver (I²C) for the Philips P90CL301micro-controller.It is not only an example of writing a driver, but it also includes a set of application interface software routines toquickly implement a complete I²C multi-master system application.For specific applications the user will have to make minimal changes in the driver program. Using the drivermeans linking modules to your application software and including a header-file into the application sourceprograms. A small example program of how to use the driver is listed.The driver supports i.a. polled or interrupt driven message handling, slave message transfers and multi-mastersystem applications. Furthermore, it is made suitable for use in conjunction with real time operating systems, likepSOS+.
上传时间： 2013-11-23
上传用户：weixiao99
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
Abstract: This application note explains the hardware of different types of 1-Wire® interfaces and software examples adapted to this hardware with a focus on serial ports. Depending on the types of iButtons required for a project and the type of computer to be used, the most economical interface is easily found. The hardware examples shown are basically two different types: 5V general interface and 12V RS-232 interface. Within the 5V group a common printed circuit board could be used for all circuits described. The variations can be achieved by different populations of components. The same principal is used for the 12V RS-232 interface. The population determines if it is a Read all or a Read/Write all type of interface. There are other possible circuit implementations to create a 1-Wire interface. The circuits described in this application note cover many different configurations. For a custom application, one of the described options can be adapted to meet individual needs.
标签： iButtons Reading Writing and
上传时间： 2013-10-29
上传用户：long14578
The 87LPC76X Microcontroller combines in a small package thebenefits of a high-performance microcontroller with on-boardhardware supporting the Inter-Integrated Circuit (I2C) bus interface.The 87LPC76X can be programmed both as an I2C bus master, aslave, or both. An overview of the I2C bus and description of the bussupport hardware in the 87LPC76X microcontrollers appears inapplication note AN464, Using the 87LPC76X Microcontroller as anI2C Bus Master. That application note includes a programmingexample, demonstrating a bus-master code. Here we show anexample of programming the microcontroller as an I2C slave.The code listing demonstrates communications routines for the87LPC76X as a slave on the I2C bus. It compliments the program inAN464 which demonstrates the 87LPC76X as an I2C bus master.One may demonstrate two 87LPC76X devices communicating witheach other on the I2C bus, using the AN464 code in one, and theprogram presented here in the other. The examples presented hereand in AN464 allow the 87LPC76X to be either a master or a slave,but not both. Switching between master and slave roles in amultimaster environment is described in application note AN435.The software for a slave on the bus is relatively simple, as theprocessor plays a relatively passive role. It does not initiate bustransfers on its own, but responds to a master initiating thecommunications. This is true whether the slave receives or transmitsdata—transmission takes place only as a response to a busmaster’s request. The slave does not have to worry about arbitrationor about devices which do not acknowledge their address. As theslave is not supposed to take control of the bus, we do not demandit to resolve bus exceptions or “hangups”. If the bus becomesinactive the processor simply withdraws, not interfering with themaster (or masters) on the bus which should (hopefully) try toresolve the situation.
上传时间： 2013-11-19
上传用户：shirleyYim
Presents short and simple I2C software routines that support onlyslave (rather than master or master & slave) operation and an ASMdemonstration program. The slave-only software in this app notecomplements the master mode software presented in AN464, Usingthe 87LPC76X microcontroller as an I2C bus master.
上传时间： 2013-11-22
上传用户：1039312764
The MC68HC05K0 is a low cost, low pin countsingle chip microcomputer with 504 bytes of userROM and 32 bytes of RAM. The MC68HC05K0 isa member of the 68HC05K series of devices whichare available in 16-pin DIL or SOIC packages.It uses the same CPU as the other devices in the68HC05 family and has the same instructions andregisters. Additionally, the device has a 15-stagemulti-function timer and 10 general purposebi-directional I/0 lines. A mask option is availablefor software programmable pull-downs on all ofthe I/O pins and four of the pins are capable ofgenerating interrupts.The device is ideally suited for remote-controlkeyboard applications because the pull-downs andthe interrupt drivers on the port pins allowkeyboards to be built without any externalcomponents except the keys themselves. There isno need for external pull-up or pull-down resistors,or diodes for wired-OR interrupts, as these featuresare already designed into the device.
上传时间： 2014-01-24
上传用户：zl5712176
CAN与RS232转换节点的设计与实现 介绍将CAN总线接口与RS232总线接口相互转换的设计方法和2种总线电平转换关系，实现CAN总线与各模块的接口设计，制定了相应的软硬件设计方案，并给出软件设计流程图以及部分硬件设计原理图。为CAN总线与RS232总线互联提供了一种方法，对CAN总线与RS232总线接口设备的互联和广泛应用的实现具有重要意义。关键词：CAN总线；RS-232总线；串行通信Design and Realization of CAN and RS232 Transformation NodeZHOU Wei, CHENG Xiao-hong(Information Institute, Wuhan University of Technology, Wuhan 430070)【Abstract】This paper introduces one design method of the CAN bus interface and the RS232 bus interface interconversion, emphasizes two kindof bus level transformation relations, realizes the CAN bus and various modules connection design, formulates the design proposal of correspondingsoftware and hardware, and gives the flow chart of software design as well as the partial schematic diagram of hardware design. It providesonemethod for the CAN bus and the RS232 bus interconnection, has the vital significance to widespread application realization of the CAN busand theRS232 bus interface equipment interconnection.【Key words】CAN bus; RS-232 bus; serial communication
上传时间： 2013-11-04
上传用户：leesuper
