上一页 1 ··· 23 24 25 26 27 28 29 30 31 ··· 34 下一页
摘要: 74HC245/74HCT245The 74HC245; 74HCT245 is a high-speed Si-gate CMOS device and is pin compatiblewith Low-Power Schottky TTL (LSTTL).The 74HC245; 74HCT245 is an octal transceiver featuring non-inverting 3-state buscompatible outputs in both send and receive directions. The 74HC245; 74HCT245features an 阅读全文
posted @ 2013-07-14 22:33 IAmAProgrammer 阅读(2750) 评论(0) 推荐(0) 编辑
摘要: http://www.amobbs.com/thread-5541344-1-2.html3.3V转5V:S3输入为0V时,NMOS管导通,S5=S3=0V;S3输入为3.3V时,NMOS管截止,S5上拉到5V;5V转3.3V:S5输入为0V时,NMOS管体二极管导通,S3=0.7V,此时NMOS管导通,S3=S5=0V;S5输入为5V时,NMOS管截止,S3上拉到3.3V。NMOS管可以选用BSS138R2可以省略,NMOS管G极可以直接连接到3.3V电源,R2的作用是改善EMI性能。AN97055I2C电平转换 阅读全文
posted @ 2013-07-14 21:58 IAmAProgrammer 阅读(1932) 评论(0) 推荐(0) 编辑
摘要: The TPS703xx family of devices is designed to provide a complete power management solution for TI DSP, processor power, ASIC, FPGA, and digital applications where dual output voltage regulators are required. Easy programmability of the sequencing function makes this family ideal for any TI DSP appli 阅读全文
posted @ 2013-07-14 21:21 IAmAProgrammer 阅读(1004) 评论(0) 推荐(0) 编辑
摘要: In need of a programmer for PIC micro controllers I decided to build my own one. This programmer has been designated as "PIC JDM Prototype Programmer 1001" because it is very likely the 1001st PIC programmer :-)The programmer is basically operating as aJDM-programmer. Any programming softw 阅读全文
posted @ 2013-07-14 01:40 IAmAProgrammer 阅读(510) 评论(0) 推荐(0) 编辑
摘要: http://www.romanblack.com/smps/conv.htmWhat is it?This is a simple smps voltage converter,it makes an output voltage of +13.3v from a "standard" +5v supply as used with logic chips.I was contacted by hobby PIC programmer legendMyke Predkoabout designing a simple and cheap circuit to produc 阅读全文
posted @ 2013-07-14 01:36 IAmAProgrammer 阅读(500) 评论(0) 推荐(0) 编辑
摘要: http://www.nomad.ee/micros/mc34063a/index.shtmlThis is a simple-minded design tool that allows you to calculate component values MC34063A simple switcher chip. It displays the appropriate scematic diagram (step-up, step-down, or inverting) and checks for current and voltage limits. Feedback resistor 阅读全文
posted @ 2013-07-14 01:29 IAmAProgrammer 阅读(317) 评论(0) 推荐(0) 编辑
摘要: http://simon.derr.free.fr/site/spip/spip.php?article11This is a description of my very simplified home-made pickit2 clone.Basically I took the schematic in the User Guide and removed everything I could.What I removed:Leds (pretty useless)The eeproms (they are not even used by the firmware)The Vdd ci 阅读全文
posted @ 2013-07-14 01:18 IAmAProgrammer 阅读(614) 评论(0) 推荐(0) 编辑
摘要: http://uzzors2k.4hv.org/index.php?page=usbpicprogMy Tait Serial programmer works alright, but not every computer has a parallel port, and these days they're almost extinct. Most laptop don't even have a serial port! Thinking ahead a USB programmer seems like a smart investment. Fortunately s 阅读全文
posted @ 2013-07-14 01:15 IAmAProgrammer 阅读(1268) 评论(0) 推荐(0) 编辑
摘要: BeeHive204 Very fast universal 4x 48-pindrive concurrent multiprogramming system with ISP capabilityBeeProg2 Very fast universal 48-pindrive Programmer with USB/LPT interface and ISP capabilityBeeProg2C Very fast universal 48-pindrive Programmer with USB interface and ISP capabilityBeeProg+ Universa 阅读全文
posted @ 2013-07-13 23:50 IAmAProgrammer 阅读(2271) 评论(0) 推荐(0) 编辑
摘要: FeaturesSEEprogis universal programmer of all types of serial EEPROMs in 8-pin package. SEEprog enables programming EEPROMs with interface types IIC (24Cxx), Microwire (93Cxx) and SPI (25Cxx). Programmer supports programming LV EEPROMs (3.3V). The programmer is equipped by ZIF socket. The quality of 阅读全文
posted @ 2013-07-13 21:59 IAmAProgrammer 阅读(666) 评论(0) 推荐(0) 编辑
摘要: http://www.elnec.com/products/universal-programmers/beeprog2c/FPGA basedtotally reconfigurable 48powerful TTL pindriversprovide H/L/pull_up/pull_down and read capability for each pin of socket. Advanced pindrivers incorporatehigh-quality high-speedcircuitry to deliver signals without overshoot or gr 阅读全文
posted @ 2013-07-13 21:57 IAmAProgrammer 阅读(640) 评论(0) 推荐(0) 编辑
摘要: http://www.elnec.com/products/universal-programmers/smartprog2/40powerful TTL pindriversprovide H/L/pull_up/pull_down and read capability for each pin of socket. Advanced pindrivers incorporatehigh-quality high-speedcircuitry to deliver signals without overshoot or ground bounce for all supported de 阅读全文
posted @ 2013-07-13 21:49 IAmAProgrammer 阅读(430) 评论(0) 推荐(0) 编辑
摘要: http://www.circuitsathome.com/mcu/pic_vpp_limiterVOUT = 2.5V * ( 1 + 24/10 ) = 2.5 * 3.4 = 8.5VNewer PIC18s, such as my current favorite – PIC18F26K20, don’t like to be programmed with 12V. The datasheet maximum is 9V. Older Microchip programmers/debuggers, such as PicKit and ICD 2, do not support v 阅读全文
posted @ 2013-07-13 21:18 IAmAProgrammer 阅读(836) 评论(0) 推荐(0) 编辑
摘要: 所有专为驱动白光LED而设计的IC都提供恒定电流夕其中尽大多数是基于电感或电荷泵的解决方案9这两种解决方案各有其优缺点。 电荷泵解决方案也称为开关电容器解决方案,利用分离电容器将电源从输进端传送至输出端,整个过程不需使用任何电感男所以是受欢迎的解决方案。电荷泵电源的体积很小,设计也很简单,选择组件时通常只需根据组件规格从中挑选适当的电容器。 电荷泵解决方案的主要缺点是它只能提供有限的输出电压范围,尽大多数电荷泵的转换比率最多只能达到输进电压的两倍,这表示输出电压不可能高于输进电压的两倍。因此,若想利用电荷泵驱动一个以上的白光LED,就必须采用并联驱动的方式。利用只能对输出电压进行稳压的电荷.. 阅读全文
posted @ 2013-07-13 21:01 IAmAProgrammer 阅读(533) 评论(0) 推荐(0) 编辑
摘要: 电感式升压转换器-AIC1896 AIC1896是一个脉冲宽度调变(Pulse-Width-Modulation;PWM)控制之升压型转换器,它可以提供一个定电流以驱动白光LED.(图五A)为升压转换器之等效电路图,当开关SW关闭时,电感L开始储存能量,此时负载端需求的能量是由输出电容所提供的,其等效电路如(图五B)所示,当开关SW打开时,原本储存在电感里的能量会连同输入电压的能量一同对输出电容充电,其等效电路如(图五C)所示图六)为AIC1896的内部构造示意图,PWM是其主要的控制模式.(图七A)描述PWM的控制方式,控制讯号VC是回馈电压(VFB)和参考电压(VREF)的比较结果,而VC 阅读全文
posted @ 2013-07-13 20:56 IAmAProgrammer 阅读(1056) 评论(0) 推荐(0) 编辑
摘要: http://learn.adafruit.com/ice-tube-clock-kit/designTubes such as VFDs, Nixies, Decatrons, etc require high voltage to light the gas in the tube. For nixies, this iabout 170VDC. VFDs aren't as bad they only need about 30-50VDC. In order to reduce cost, we use the microconrtoller to make a boost c 阅读全文
posted @ 2013-07-13 20:53 IAmAProgrammer 阅读(576) 评论(0) 推荐(0) 编辑
摘要: http://blog.csdn.net/muge0913/article/details/6741064VCC,VDD,VEE,VSS,VPP表示的意义版本一:简单说来,可以这样理解:一、解释VCC:C=circuit 表示电路的意思, 即接入电路的电压;VDD:D=device 表示器件的意思, 即器件内部的工作电压;VSS:S=series 表示公共连接的意思,通常指电路公共接地端电压;VEE:负电压供电;VPP:编程/擦除电压。二、说明1、对于数字电路来说,VCC是电路的供电电压,VDD是芯片的工作电压(通常Vcc>Vdd),VSS是接地点。2、有些IC既有VDD引脚又有VCC引 阅读全文
posted @ 2013-07-13 16:07 IAmAProgrammer 阅读(2377) 评论(0) 推荐(0) 编辑
摘要: 征一个简单、可靠的电源过压保护电路http://www.amobbs.com/thread-5542005-1-1.html防过压:过压之后TVS导通,电流由正极流经自恢复保险再流经TVS到负极,自恢复保险升温,阻值变大,相当于断开,等电流撤去,自恢复保险温度下降,恢复导通防反接:反接时TVS直接导通,自恢复保险断开。如果觉得反应速度不够快的话,可以在二次侧并联一个比较大的电容,减慢电压上升速度。另外有个单一元件叫ZEN056V130A24LS,也是类似原理实现上述功能,datasheet如下TE PolyZen Devices 产品性能选择请见http://www.te.com.cn/cat 阅读全文
posted @ 2013-07-13 15:38 IAmAProgrammer 阅读(1225) 评论(0) 推荐(0) 编辑
摘要: http://www.daxia.com/bibis/moredata30_1207792_29862.shtml图中DA和PWM任选其一, 当DA或PWM输出为0~1.25V时,输出在12.5V~5V之间可调。实际上,DA输出到1.875V时,输出可以调至1.25V将3K电阻改成7.68K,可以输出到1.25~30VMG_wmj,2576内部的参考电压1.23V跟外面的DA电压及Vout电压之间怎讲计算的??另外,如果用DA的话,PWM及运放电路可以去掉吗?VOUT=((Vref/R1)-(Vda-Vref)/R2)*R3+Vref其中:R1为Vref端对地电阻;R2为DA输出串联电阻;R3 阅读全文
posted @ 2013-07-13 15:25 IAmAProgrammer 阅读(9783) 评论(0) 推荐(0) 编辑
摘要: http://bbs.ednchina.com/BLOG_ARTICLE_3013105.HTMLM2677,是TI公司生产的高效率5A开关buck稳压器,由于它内部具备的lowON-registerDMOS功率开关,使得它能够驱动大电流负载。LM2677有+3.3V、+5V、+12V和AJUSTABLE四个版本,其中AJUSTABLE的输出范围是1.2V~37V,使用它可以做一个可调的恒压源。官方手册中给出的AJUSTABLE典型应用电路如下:在上图中,R1固定为1K,选择不同的R2值,就能得到不同的输出电压。VOUT=VREF*(R1+R2)/R1其中VREF=1.21V。如果需要得到14 阅读全文
posted @ 2013-07-13 12:20 IAmAProgrammer 阅读(3346) 评论(0) 推荐(0) 编辑
摘要: http://blog.sina.com.cn/s/blog_4d144f6d0100clem.html电压跟随器的显著特点就是,输入阻抗高,而输出阻抗低,一般来说,输入阻抗要达到几兆欧姆是很容易做到的。输出阻抗低,通常可以到几欧姆,甚至更低。 在电路中,电压跟随器一般做缓冲级及隔离级。因为,电压放大器的输出阻抗一般比较高,通常在几千欧到几十千欧,如果后级的输入阻抗比较小,那么信号就会有相当的部分损耗在前级的输出电阻中。在这个时候,就需要电压跟随器来从中进行缓冲。起到承上启下的作用。应用电压跟随器的另外一个好处就是,提高了输入阻抗,这样,输入电容的容量可以大幅度减小,为应用高品质的电容提供了前 阅读全文
posted @ 2013-07-13 12:01 IAmAProgrammer 阅读(5376) 评论(0) 推荐(0) 编辑
摘要: http://home.eeworld.com.cn/my/space-uid-425020-blogid-82340.html对应运放“虚短”、“虚断”和“虚地”三个概念,你知道多少?我们知道,由于运放的电压放大倍数很大,一般通用型运算放大器的开环电压放大倍数都在80 dB以上。而运放的输出电压是有限的,一般在 10V~14V。因此运放的差模输入电压不足1 mV,两输入端近似等电位,相当于 “短路”。开环电压放大倍数越大,两输入端的电位越接近相等。 ⑴虚短:集成运放的线性应用时,可近似地认为uN-uP=0,uN=uP时,即反相与同相输入端之间相当于短路,故称虚假短路,简称“虚短”。“虚短”. 阅读全文
posted @ 2013-07-13 10:48 IAmAProgrammer 阅读(29976) 评论(0) 推荐(3) 编辑
摘要: http://www.freelabs.com/~whitis/electronics/jtag/Each JTAG enabled chip has a TAP controller with a state machine with 16 states.The state of the TMS pin at each TCK pulse dictates the transitions between states. These states help control whether you are shifting through the instruction register or 阅读全文
posted @ 2013-07-12 15:29 IAmAProgrammer 阅读(4413) 评论(0) 推荐(0) 编辑
摘要: http://www.jtagtest.com/pinouts/PinoutsARM-20(used with almost all ARM-based microcontrollers)ARM-14(used as a lower pin-count version of ARM-20)MIPS EJTAGused with all MIPS microcontrollers (mostly embedded devices, can be found on many WiFi devices)Toshiba MIPSPhilips MIPSAVR JTAGCompatible with A 阅读全文
posted @ 2013-07-12 13:36 IAmAProgrammer 阅读(2161) 评论(0) 推荐(0) 编辑
摘要: 6.4 Device Error HandlingThe device may not be able to fully satisfy the host's request.At the point when the device discovers that itcannot fully satisfy the request,there may be a Data-In or Data-Out transfer in progress on the bus,and the hostmay have other pending requests.The device may cau 阅读全文
posted @ 2013-06-30 23:49 IAmAProgrammer 阅读(1004) 评论(0) 推荐(0) 编辑
摘要: http://stackoverflow.com/questions/14363152/send-custom-commands-to-mass-storage-deviceI have developed a mass-storage device, and I'd a like a PC application to send/receive some custom commands to it. Normally one would create a composite USB device for this (MSC+HID) and send the commands ove 阅读全文
posted @ 2013-06-30 23:20 IAmAProgrammer 阅读(3180) 评论(0) 推荐(0) 编辑
摘要: http://social.msdn.microsoft.com/Forums/windowsdesktop/zh-CN/35620a05-43be-46a8-8cbe-846bc8295d85/usb-mass-storage-cWe have an USB mass storage / Memory Stick device with an additional device on it. We communicate with PassThrough mechanism to the device.Normally USB spec says that on USB level not 阅读全文
posted @ 2013-06-30 23:04 IAmAProgrammer 阅读(1565) 评论(0) 推荐(0) 编辑
摘要: http://arm-utilities.googlecode.com/svn-history/r47/trunk/stlink-download/stlink-download.c/* STLink download/debug interface for Linux. *//* This program interacts with the STMicro USB STLink programming/debug interface for STMicro microcontrollers. The STLink is found on STM8 and STM32VLDiscovery. 阅读全文
posted @ 2013-06-30 22:56 IAmAProgrammer 阅读(2993) 评论(0) 推荐(0) 编辑
摘要: http://code.msdn.microsoft.com/SCSI-Pass-Through-a906ceef/sourcecode?fileId=59048&pathId=1919073465http://code.msdn.microsoft.com/SCSI-Pass-Through-a906ceef/file/59048/13/SCSI%20Pass-Through%20Interface%20Tool.zip/*++ Copyright (c) 1992 Microsoft Corporation Module Name: spti.h Abstract: ... 阅读全文
posted @ 2013-06-30 22:49 IAmAProgrammer 阅读(3528) 评论(0) 推荐(0) 编辑
摘要: http://www.ezblog.idv.tw/Download/USBStorage.rar這是一個不透過檔案系統,去讀寫USB Mass Storage 任何位置(包含FAT)的方式首先需安裝微軟的DDK並include "usbioctl.h" , "usbdi.h" , "ntddscsi.h"有幾個資料結構要定義typedef struct _SCSI_Device_Info_{ SCSI_PASS_THROUGH Spt; BYTE Sense[ 18 ]; BYTE Data[ 36 ];} SCSI_Device_I 阅读全文
posted @ 2013-06-30 22:44 IAmAProgrammer 阅读(2075) 评论(0) 推荐(0) 编辑
摘要: http://cutebunny.blog.51cto.com/301216/674443最近碰到了个新问题,记录下来作为windows的磁盘操作那个系列的续篇吧。一些时候我们的程序需要区分本地存储设备和USB存储设备。在网上搜一搜一般会找到一个最直接的API,GetDriveType,其原型为UINT GetDriveType(LPCTSTR lpRootPathName)参数lpRootPathName是存储设备的根目录,例如C:\,返回值即为设备类型。Return codeDescriptionDRIVE_REMOVABLEThe drive has removable media; f 阅读全文
posted @ 2013-06-30 22:27 IAmAProgrammer 阅读(3081) 评论(0) 推荐(0) 编辑
摘要: http://bbs3.driverdevelop.com/simple/?t84347.html{ BOOL status = 0; DWORD accessMode = 0, shareMode = 0; HANDLE fileHandle = NULL;//PUCHAR dataBuffer = NULL; SCSI_PASS_THROUGH_WITH_BUFFERS sptwb; SCSI_PASS_THROUGH_DIRECT_WITH_BUFFER sptdwb; UCHAR buffer[ 2048 ]; UCHAR string[ 25 ]; ULONG len... 阅读全文
posted @ 2013-06-30 22:21 IAmAProgrammer 阅读(4811) 评论(0) 推荐(0) 编辑
摘要: http://flyxxtt.blogbus.com/logs/43181576.html函数原型:UINTGetDriveType(LPCTSTR lpRootPathName)参数lpRootPathName是根目录,如"C:\",一定要加上反斜杠。如果给此参数传入NULL将返回程序当前目录的驱动器类型。返回值所代表的类型请看下面的例子。使用例子:wstring getDriveType( LPCTSTR lpRootPathName ){ wstring typename; unsigned int type = GetDriveType( _T( "C:\ 阅读全文
posted @ 2013-06-30 22:19 IAmAProgrammer 阅读(2554) 评论(0) 推荐(0) 编辑
摘要: http://banderlogi.blogspot.com/2011/06/enum-drive-letters-attached-for-usb.htmltypedef enum _STORAGE_BUS_TYPE { BusTypeUnknown = 0x00, BusTypeScsi = 0x01, BusTypeAtapi = 0x02, BusTypeAta = 0x03, BusType1394 = 0x04, BusTypeSsa = 0x05, BusTypeFibre... 阅读全文
posted @ 2013-06-30 22:15 IAmAProgrammer 阅读(1823) 评论(0) 推荐(0) 编辑
摘要: http://www.jubao163.com/it/bianchengwendang/2007-06-17/14948.shtmltypedef struct _SCSI_PASS_THROUGH{ USHORT Length; UCHAR ScsiStatus; UCHAR PathId; UCHAR TargetId; UCHAR Lun; UCHAR CdbLength; UCHAR SenseInfoLength; UCHAR DataIn; ULONG DataTransferLength; ULONG TimeOutValue; ULONG_PTR Data... 阅读全文
posted @ 2013-06-30 22:12 IAmAProgrammer 阅读(777) 评论(0) 推荐(0) 编辑
摘要: http://fx.damasgate.com/more-about-stall/In other USB classes, a sender can indicate the end of a transfer by transmitting a short packet, which is a data packet that contains zero data bytes or any quantity fewer than wMaxPacketSize.The mass-storage class is unique in its use of the STALL handshake 阅读全文
posted @ 2013-06-30 11:33 IAmAProgrammer 阅读(457) 评论(0) 推荐(0) 编辑
摘要: http://210.240.55.2/~t311/moe/engb5/b5grammar/b5tooeither.htm本单元中所谈论的是「也」在英文中的讲法:英文中的「也」共有五种说法,分别是too/either 、 so/neither,及also:(一)too/either:肯定的用too;否定的用either;两者均是放在句尾,且其前加逗号。eg1. He is a student,andI am (a student),too.2. Susan collected stamps,andher sister did/collected stamps,too.3. John doesn 阅读全文
posted @ 2013-06-30 00:06 IAmAProgrammer 阅读(2693) 评论(0) 推荐(0) 编辑
摘要: http://www.yywords.com/Article/200806/347.html1.这三个词都用来谈论两者:both意为“(两者)都”,either意为“(两者中)任意一个”,neither意为“(两者)都不”。若要指三者或三者以上,分别用all意为“(三者)都”,any意为“(三者中)任何一个”,none意为“(三者)都不”等。比较:He has two sons; both of them are clever.He has two sons; either of them is clever.He has two sons; neither of them is clever 阅读全文
posted @ 2013-06-29 23:48 IAmAProgrammer 阅读(3165) 评论(0) 推荐(0) 编辑
摘要: http://msdn.microsoft.com/zh-cn/library/ae5bf541(v=vs.80).aspx正则表达式是一种文本模式,包括普通字符(例如,a 到 z 之间的字母)和特殊字符(称为“元字符”)。模式描述在搜索文本时要匹配的一个或多个字符串。正则表达式示例表达式匹配/^\s*$/匹配空行。/\d{2}-\d{5}/验证由两位数字、一个连字符再加 5 位数字组成的 ID 号。/]*)?>[\s\S]*/匹配 HTML 标记。下表包含了元字符的完整列表以及它们在正则表达式上下文中的行为:字符说明\将下一字符标记为特殊字符、文本、反向引用或八进制转义符。例如,“n” 阅读全文
posted @ 2013-06-28 10:30 IAmAProgrammer 阅读(855) 评论(0) 推荐(0) 编辑
摘要: http://code.riaos.com/?p=5011676硬盘按照存储介质分为机械硬盘(HDD)和固硬盘(SSD)硬盘的数据接口主要分为以下几种 :ATA(IDE):从ATA1 到ATA7, 兼容性比较好,采用40pin并口数据线SATA:ATA的继任者,串行的ATA接口,采用4pin的数据线,支持热插拔SCSI:小型机系统接口,支持高转速的硬盘,传输时占用CPU资源较低,有50pin,68pin,80pin多种规格SAS:串行 SCSI,是由SCSI演化过来的,比SCSI更快并且配置更简单。兼容SATA设备,可以使用相同的电缆。SATA的硬盘可以接在SAS接口上使用硬盘的电源接口主要和 阅读全文
posted @ 2013-06-27 13:49 IAmAProgrammer 阅读(1484) 评论(0) 推荐(0) 编辑
上一页 1 ··· 23 24 25 26 27 28 29 30 31 ··· 34 下一页